PROFIBUS-PA PROFIBUS-DP. Field Communication PROFIBUS-DP/PA: Guidelines for planning and commissioning

Transcription

1 PROFIBUS-PA PROFIBUS-DP Field Communication PROFIBUS-DP/PA: Guidelines for planning and commissioning

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3 Profibus-DP/PA Overview able of Contents able of Contents Notes on Safety Introduction Advantages of a bus system PROFIBUS standard PROFIBUS in process engineering PROFIBUS-DP Basics Synopsis opology Bus access method Network configuration Applications in hazardous areas PROFIBUS-PA Basics Synopsis Segment couplers and links opology Bus access method Network configuration Applications in hazardous areas Planning Selection of the segment coupler Cable type and length Calculation of current consumption Voltage at last device Calculation examples for bus design Data quantity Cycle times Addressing Example calculations for addressing and cycle times Installation Cabling in safe areas Example: screening in safe areas Example: screening in explosion hazardous areas ermination Overvoltage protection Installation of the devices Addressing Notes on network design ested system integrations Bus parameters Device Configuration PROFIBUS-PA block model Device management Physical block ransducer blocks Function blocks Operating program Commuwin II Operating Simatic PDM rouble-shooting Commissioning PLC planning Data transmission Commuwin II echnical Data PROFIBUS-DP PROFIBUS-PA PROFIBUS-PA Components Endress+Hauser and Metso field devices Network components Supplementary documentation erms and Definitions Bus architecture Components Data exchange Miscellaneous terms Appendix Calculation sheets for explosion hazardous areas EEx ia Calculation sheets for explosion hazardous areas EEx ib Calculation sheets for non-hazardous areas Index System Integration Device database files (GSD) Data format Metso Endress+Hauser 1

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5 Notes on Safety hese operating instructions are intended as a planning aid for the use of Endress+Hauser and Metso devices in PROFIBUS-PA systems. he approved usage of the individual devices can be taken from the corresponding device operating instructions. he field devices, segment coupler, cables and other components must be designed to operate safely in accordance with current technical safety and EU standards. If installed incorrectly or used for applications for which they are not intended, it is possible that dangers may arise. For this reason, the system must be installed, connected, operated and maintained according to the instructions in this manual: personnel must be authorised and suitably qualified. If the system is to be installed in an explosion hazardous area, then the specifications in the certificate as well as all national and local regulations must be observed. Approved usage Installation, commissioning, operation Explosion hazardous area Ensure that all personnel are suitably qualified Observe the specifications in the certificate as well as national and local regulations. For PROFIBUS-PA all components should be designed in accordance with the FISCO model. his greatly simplifies the acceptance testing of the PROFIBUS-PA segment. PROFIBUS-PA Guidelines Notes on Safety Endress+Hauser and Metso reserves the right to make technical improvements to its equipment at any time and without prior notification. Where such improvements have no effect on the operation of the equipment, they are not documentated. If the improvements effect operation, a new version of the operating instructions is normally issued. echnical improvement Metso Endress+Hauser 3

6 Safety conventions and symbols In order to highlight safety-relevant or alternative operating procedures in the manual, the following conventions have been used, each indicated by a corresponding icon in the margin. Safety conventions Symbol Meaning Note! A note highlights actions or procedures which, if not performed correctly, may indirectly affect operation or may lead to an instrument response which is not planned Caution! Caution highlights actions or procedures which, if not performed correctly, may lead to personal injury or incorrect functioning of the instrument Warning! A warning highlights actions or procedures which, if not performed correctly, will lead to personal injury, a safety hazard or destruction of the instrument Explosion protection Device certified for use in explosion hazardous area If the device has this symbol embossed on its name plate it can be installed in an explosion hazardous area Explosion hazardous area Symbol used in drawings to indicate explosion hazardous areas. Devices located in and wiring entering areas with the designation ìexplosion hazardous areasî must conform with the stated type of protection Safe area (non-explosion hazardous area) Symbol used in drawings to indicate, if necessary, non-explosion hazardous areas. Devices located in safe areas stiill require a certificate if their outputs run into explosion hazardous areas. Electrical symbols Direct voltage A terminal to which or from which a direct current or voltage may be applied or supplied Alternating voltage A terminal to which or from which an alternating (sine-wave) current or voltage may be applied or supplied Grounded terminal A grounded terminal, which as far as the operator is concerned, is already grounded by means of an earth grounding system Protective grounding (earth) terminal A terminal which must be connected to earth ground prior to making any other connection to the equipment Equipotential connection (earth bonding) A connection made to the plant grounding system which may be of type e.g. neutral star or equipotential line according to national or company practice 4 Metso Endress+Hauser

7 1 Introduction hese guidelines have been written with the view of giving the potential PROFIBUS user an introduction to the planning and commissioning of a PROFIBUS-PA network. hey are based on the experience of Endress+Hauser and Metso employees who have been actively involved in PROFIBUS projects and who, in the meantime, have successfully commissioned a number of plants. he guidelines are structured as follows: Application Chapter itel Inhalt Chapter 1 Introduction Advantages of a bus as well as general information about the PROFIBUS standard Chapter 2 PROFIBUS-DP basics Information about PROFIBUS-DP Chapter 3 PROFIBUS-PA basics Information about PROFIBUS-PA, couplers, links and use in explosion hazardous areas (FISCO-Model) Chapter 4 Planning What must be observed when planning PROFIBUS-DP/PA systems, with examples Chapter 5 Installation Notes on the installation of devices in a PROFIBUS-DP/PA system Chapter 6 System integration Notes on mapping PROFIBUS-PA devices in a PLC Chapter 7 Device configuration General information on setting the parameters in Endress+Hauser devices PROFIBUS applications Chapter 8 rouble-shooting Causes and remedies for general faults that may occur during the commissioning of a system Chapter 9 echnical data Principle technical data of PROFIBUS-PA and PROFIBUS-DP Chapter 10 PROFIBUS-PA components Profiles of the Endress+Hauser PROFIBUS-DP and PROFIBUS-PA devices Chapter 11 erms and definitions Explanation of the terminology used to describe bus systems Chapter 12 Appendix Calculation sheets for your applications Should you have any questions regarding PROFIBUS which go beyond the subjects discussed in this manual, do not hesitate to get in touch with us. Metso Endress+Hauser 5

8 1.1 Advantages of a bus system Conventional PROFIBUS-PA process-near component PNC I/O assemblies process-near component PNC bus coupler Ex [i] marshalling rack Ex [i] power Control room marshalling rack junction box connectors Fig. 1.1 Signal transfer: conventional and with PROFIBUS-PA Field Wiring Figure 1.1 illustrates the difference between the wiring of a conventional ma control system and a fieldbus system. For a compact plant, the wiring from the field to the junction box is roughly the same: if the measuring points are widely distributed, however, the fieldbus requires decidedly less cable. For conventional wiring, every signal line must be continued from the junction box to the process-near component, e.g. a programmable logic controller, where it terminates in a I/O module. For every device a separate power supply is required, where necessary, suitable for use with devices in hazardous areas. In contrast, the fieldbus requires a single cable only to carry all information. he bus terminates in a bus coupler that communicates directly with the process near components. Not only cable, but also I/O modules are saved. Since the bus is powered from a single intrinsically safe power unit, there is no need for individual isolators and barriers. Commissioning Operation Maintenance Digital communication allows comfortable commissioning of field devices from the control room. Individual devices can not only be configured from a personal computer but the settings can also be archived centrally. If there are several identical measuring points in an application, the stored parameters can be downloaded to the devices. An individual configuration of each device is no longer necessary. In addition to the process variables and setpoints that are processed in the programmable logic controller (PLC) or process control system (PCS), the operator has access to a number of other parameters at every measuring and control point. hese can be displayed in the Commuwin II operating and display program or a SCADA application or any asset management software, such as Siemens Simatic PDM. he programs offer a clear overview of the application. Devices with diagnosis functions or self-monitoring signal faults to the bus master. he status of each device can be checked from the control room, so that the maintenance team can quickly localise and eliminate the fault. 6 Metso Endress+Hauser

9 1.2 PROFIBUS standard PROFIBUS is an open fieldbus standard to EN It was developed by a German consortium that quickly and pragmatically produced the German Standard DIN after attempts to produce an international fieldbus failed in he European Standard followed roughly a year later. PROFIBUS is supported by an international network of PROFIBUS User Organisations. PROFIBUS-DP (decentralised periphery) is an extension of the original PROFIBUS standard, see Fig An extension contains a subset of the functionality of the original standard and is targeted at a specific area of application. PROFIBUS-DP was primarily developed for the fast processes involved in factory automation. In the original version, PROFIBUS-DP allowed only one master that communicated via the master-slave method. he extended version DPV1 allows up to 127 participants including up to 32 masters. A slave, however, may be allocated to only one "Class 1" master, see Chapter 2. Slaves are configured by a Class 2 master using acyclic services. PROFIBUS-PA (process automation) is an extension of PROFIBUS-DP for process automation. It has two specialities: firstly, participants can draw intrinsically safe power from the bus, secondly, the data transfer is handled according to the international standard IEC A maximum of 32 participants can be connected to a PROFIBUS-PA segment. Bus access is governed by the master/slave method, see Chapter 3. PROFIBUS-DP PROFIBUS-PA FMS DP PA OSI layer FMS device profile DP profile PA profile DP extensions (DPV1) User DP basic functions Application (7) Fieldbus message specification FMS (3) (6) BA198Y55 Data (2) physical (1) Fieldbus data link (FDL) RS-485/fibre optics IEC interface IEC Fig. 1.2 PROFIBUS versions and functions Metso Endress+Hauser 7

10 0-10 bar 0-10 bar 0-10 bar 0-10 bar PROFIBUS-PA Guidelines 1.3 PROFIBUS in process engineering Commuwin II SPS Process Control System RS Mbit/s PROFIBUS-DP Non-hazardous Area IEC ,25 kbit/s DP/PA link or segment coupler Hazardous Area PROFIBUS-PA IEC ,25 kbit/s Fig. 1.3 Process automation with PROFIBUS-DP and PROFIBUS-PA BA198y27 Every manufacturing facility has tasks which are associated with process and factory automation: Process automation: measurement, actuation, control... Factory automation: filling, storage, conveyance, drives... For this reason it is possible that the Endress+Hauser devices installed in a factory are integrated in PROFIBUS-DP, PROFIBUS-PA or mixed systems. Fig. 1.3 shows a typical example: he process is controlled by a process control system or a programmable logic controller (PLC). he control system or PLC serves as a Class 1 master. It uses the cyclic services to acquire measurements and output control commands. he operating program, in this case Commuwin II, serves as a Class 2 master. It uses the acyclic services and serves to configure the bus participants during installation and normal operation. he PROFIBUS-DP system is used to handle the communication at the control level. Drives, remote I/Os etc. may all be found upon the bus. It is also possible to connect externally powered field devices to this level, e.g. the flowmeters Promass and Promag. PROFIBUS-DP ensures that data are quickly exchanged, whereby in mixed PROFIBUS-DP/PA systems the baudrate supported by the segment coupler is often the limiting factor. PROFIBUS-PA is used at field level. he segment coupler serves both as interface to the PROFIBUS-DP system and as power supply for the PROFIBUS-PA field devices. Depending upon the type of segment coupler, the PROFIBUS-PA segment can be installed in safe or hazardous areas. 8 Metso Endress+Hauser

11 2 PROFIBUS-DP Basics As far as PROFIBUS systems in process engineering are concerned, the versions PROFIBUS-DP (variant DPV1) and PROFIBUS-PA are of interest. his chapter describes the basics of PROFIBUS-DP. he chapter is structured as follows: Synopsis opology Bus access method Network configuration Applications in hazardous areas 2.1 Synopsis Class 1 master Class 2 master PROFIBUS-DP PROFIBUS-DP slaves BA198Y46 PROFIBUS-DP is used primarily for factory automation. In PROFIBUS-PA systems for process automation, a PROFIBUS-DP system is used at the control level for quick transmission of the data. Here, a variant of PROFIBUS-DP, DPV1 is used. In addition to the cyclic exchange of data with a PLC, this allows the field devices to be configured via acyclic services. he principle technical data for DPV1 are listed in able 2.1. Depending upon the application at hand, the participants in a PROFIBUS-DP system might be frequency converters, remote I/Os, actuators, sensors, links, gateways etc. as well as the PLC or process control system. he following Endress+Hauser devices can be connected directly to a DP system: Fig. 2.1 PROFIBUS-DP system, Version DPV1 Application Participants Flowmeters Promass 63 and Promag 33/35 Display unit Memograph RSC 10 (listener function only) PROFIBUS-DP gateway. Others are in preparation. Standard Support Physical layer Max. length Participants ransmission rate Bus access method EN 50170, Parts 1-3, Version DPV1 PROFIBUS User Organisation (PNO) RS-485 and/or fibre optics 1200 m (copper) or several kilometres (optics) Max. 126, including max. 32 as master up to 12 MBit/s oken passing with master-slave able 2.1 echnical data PROFIBUS-DP Metso Endress+Hauser 9

12 2.2 opology PROFIBUS-DP is based on a linear topology. For lower data transmission rates, a tree structure is also possible. Cable EN specifies two types of bus cable. For transmission rates up to 12 Mbit/s, cable type A is recommended. he specification is given in able 2.2. able 2.2 Specifications of Cable ype A of the PROFIBUS-DP standard erminator Cable capacitance Core cross-section Cable type Loop resistance Signal attenuation Screening 135 W to 165 W at a measuring frequency of 3 MHz to 20 MHz < 30pF per Meter >0.34 mm 2, corresponds to 22 AWG twisted pairs, 1x 2, 2x 2 or 1x 4 core 110 Ω per km max. 9 db over the entire Length of the segment woven copper sheath or woven sheath and foil sheath Structure he following points should be noted when the bus structure is being planned: he max. permissible cable length depends upon the transmission rate. For PROFIBUS RS-485 cable of type A (see table 2.2) the dependency is as follows: ransmission rate (kbit/s) Cable length (m) A maximum of 32 participants per segment is allowed. A terminating resistance must be installed at both ends of every segment (ohmic load 220 Ω) he cable length and/or the number of participants can be increased by using repeaters. here must never be more than three repeaters between any two participants. he total number of participants in the system is limited to 126 (2x number of repeaters). Spurs Examples A spur is the cable connecting the field device to the -box. As a rule of thumb: For transmission rates up to 1500 kbits/s, the total length (sum) of the spurs may not exceed 6.6 m. Spurs should not be used for transmission rates greater than 1500 kbits/s. Figs 2.2 and 2.3 show examples for a linear and tree bus structure. Fig 2.2. shows that three repeaters are necessary if the PROFIBUS-DP system is to be developed to the full. he maximum cable length corresponds to 4x the value quoted in the table above. Since three repeaters are used, the maximum number of participants is reduced to 120. Fig 2.3 shows how several repeaters can be used to create a tree structure. he number of participants allowable per segment is reduced by one per repeater: the total number of participants is limited to 126 (2x number of repeaters). 10 Metso Endress+Hauser

13 trunk cable R1 segment 1 R segment segment R3 Fig. 2.2 PROFIBUS-DP system with linear structure = terminator R = repeater 1...n = max. number of field devices on a segment trunk cable R1 segment R3 R segment 2 31 segment 3 29 Fig. 2.3 PROFIBUS-DP system with tree structure = terminator R = repeater 1...n = max. number of field devices on a segment If the PROFIBUS-DP system has to be routed over large distances or in plant with heavy electromagnetic interference, then an optical or mixed optical/copper network can be used. Provided that all participants support them, very high transmission rates are possible. Fig. 2.4 shows a possible structure for an optical network, whereby the technical details can be taken from the PROFIBUS standard. Optical network Master PLC RS-485 copper optical interface module optical interface module RS-485 copper fibre optics Fig. 2.4 Example for a mixed optical/rs-485 network = terminator 1...n = field devices (slaves) Metso Endress+Hauser 11

14 2.3 Bus access method PROFIBUS-DP uses a hybrid access method of centralised master/slave and decentralised token passing, see Fig.2.5. he masters build a logical token ring. When a master possesses the token, it has the right to transmit. It can now talk with its slaves in a master-slave relationship for a defined period of time. At the end of this time, the token must be passed on to the next active device in the token ring. Master class Version DPV1 of PROFIBUS-DP differentiates between two classes of master: A Class 1 master communicates cyclically with its slaves. he master communicates only with those slaves that are assigned to it. A slave may be assigned to only one Class 1 master. A typical class 1 master is a programmable logic controller (PLC) or a process control system. A Class 2 master communicates acyclically with its slaves, i.e. on demand. Its slaves may also be assigned to a Class 1 master. A typical example is a PC with corresponding operating software, e.g. Commuwin II. It is used for commissioning as well as for device configuration, diagnosis and alarm handling during normal operation. If a PROFIBUS-DP network has more than one master e.g. because both cyclic and acyclic services are required, then it is a multi-master system. If, for example, a PLC only is used for control tasks, then the system is a mono-master system. Master 1, Class 1 has the right to transmit Data are exchanged cyclically. M1 Class 1 M2 logical token ring S1 S2 S3 S4 S5 Master 2, Class 2 receives the right to transmit. It can talk to all slaves. Data exchange, e.g. with slave 3 is acyclic. M1 Class 2 M2 Fig. 2.5 Data exchange in a PROFIBUS-DP multi-master system M = master S = slave S1 S2 S3 S4 S5 BA198Y32 12 Metso Endress+Hauser

15 2.4 Network configuration Data are exchanged over PROFIBUS-DP by means of standard telegrams which are transmitted via the RS-485 interface. he permissible telegram length depends upon the master used: at the moment, masters are available that transmit 122 or 244 bytes, see Chapter 6, able 6.3. Data ransmission he majority of Endress+Hauser devices transmit measured value and status in 5 bytes, see table 6.1 on page 51. An instrument with several measured values transmits correspondingly more bytes. In the case of the flowmeter Promass 63, for example, a cyclic telegram of 51 bytes (50 bytes input and 1 byte output data) is transmitted at maximum configuration, see below. By using the data exchange service, a PLC can transmit its output data to the Promass 63 and read the input data from the response telegram. he cyclic data telegram for the maximum configuration of the Promass has the following structure: If the factory setting is used, mass flow, totalisor 1 and density are transmitted. Further measured values can be activated via the on-site elements or by using a PROFIBUS configuration program. Byte Data Access Data format Unit 0-3 Mass flow Read 32-bit floating point number (IEEE 754) kg/s 4 Status mass flow Read 80h = OK 5-8 otalisor 1 Read 32-bit floating point number (IEEE 754) kg 9 Status totalisor 1 Read 80h = OK Density Read 32-bit floating point number (IEEE 754) kg/m 3 14 Status density Read 80h = OK emperature Read 32-Bit floating point number (IEEE 754) K 19 Status temperature Read 80h = OK otalisor 2 Read 32-bit floating point number (IEEE 754) off 24 Status totalisor 2 Read 80h = OK Volumetric flow Read 32-bit floating point number (IEEE 754) l/s 29 Status volumetric flow Read 80h = OK Standard volumetric flow Read 32-bit floating point number (IEEE 754) Nl/s 34 Status standard volumetric flow Read 80h = OK arget medium flow Read 32-bit floating point number (IEEE 754) kg/s; l/s 39 Status target medium flow Read 80h = OK Carrier medium flow Read 32-bit floating point number (IEEE 754) kg/s; l/s 44 Status carrier medium flow Read 80h = OK Calculated density Read 32-bit floating point number (IEEE 754) % 49 Status calculated density Read 80h = OK 49 Status calculated density Read 80h = OK able 2.3 Input data Promass SPS Byte Data Access Data format Unit 0 Control 0 1: Reset totalisor 1 0 2: Reset totalisor 2 0 3: Reset totalisor : Zero point calibration 0 5: Positive zero return on 0 6: Positive zero return off : reserved Write Integer8 he control command is triggered by a change in the input data of the cyclic services from 00h to another value. A change from any bit pattern to 00h has no effect. able 2.4 Output data PLC Promass Metso Endress+Hauser 13

16 Device database file Bus address ransmission rate Bus parameters In order to integrate the field devices into the bus system, the PROFIBUS-DP system requires a description of the device parameters such as output data, input data, data format, data length and the transmission rates supported. hese data are contained in the device database file (the so-called GSD file), which is required by the PROFIBUS- DP master during the commissioning of the communication system. In addition, device bitmaps are required, which appear as icons in the network tree. Further information on device database files is to be found in Chapter 6.1. A prerequisite for communication on the bus is the correct addressing of the participants. Every participant in the PROFIBUS-DP system is assigned a unique address between 0 and 125. Normally the low addresses are assigned to the masters. he addresses may be assigned by DIP switch, on-site operating elements or by an operating program. he addressing procedure is described in detail in Chapter 5. All participants in a PROFIBUS-DP system must support the governing transmission rate. his means that the speed of data exchange is determined by the slowest participant. In the case of Endress+Hauser devices that are designed for PROFIBUS- DP, all transmission rates from 9.6 kbits/s to 12 Mbit/s are supported. In addition to the transmission rate, all active participants on the bus must operate with the same bus parameters. For the operating and display program Commuwin II, the bus parameters can be set by using the DPV1 server, see Chapter 6.5. he program can be started from the icon in the program group Commuwin II. 14 Metso Endress+Hauser

17 0-10 bar PROFIBUS-PA Guidelines 2.5 Applications in hazardous areas All devices and terminators that are installed in hazardous areas as well as all associated electrical apparatus (e.g. PA links or segment couplers) must be approved for the corresponding atmospheres. If a PROFIBUS-DP segment is routed through an explosion hazardous area, then it must be realised with type of protection "enhanced safety e". For copper cable, the number of devices per segment is limited to four. he intrinsic safety must always be calculated because every intrinsically safe component has different values. he trunk cable and spurs must be included in the calculation. he exchange of a device by the product of another manufacture means that proof of intrinsic safety must be presented again. Since PROFIBUS-PA systems are designed for use in hazardous areas, it is much easier install a segment there. For this reason, a PROFIBUS-PA segment is often used to extend the PROFIBUS-DP segment into a hazardous area. In order to obtain the highest possible transmission rate, a link is preferred as interface. Links support a wide range of PROFIBUS-DP transmission rates. Mixed network PROFIBUS-DP/PA PLC Class 1 master e.g. Commuwin II Class 2 master DP/PA link PROFIBUS-DP PROFIBUS-PA PROFIBUS-PA slaves PROFIBUS-DP slaves Fig. 2.6 he PROFIBUS-PA system can be extended into a hazardous area by using a DP/PA link. Metso Endress+Hauser 15

18 0-10 bar PROFIBUS-PA Guidelines 3 PROFIBUS-PA Basics his chapter presents the basic principles behind PROFIBUS-PA. he chapter is structured as follows: Synopsis Segment couplers and links opology Bus access method Network configuration Applications in hazardous areas 3.1 Synopsis Class 1 master Class 2 master DP/PA link or segment coupler PROFIBUS-DP PROFIBUS-PA PROFIBUS-PA slaves Fig. 3.1 PROFIBUS-PA system Application Participants PROFIBUS-PA has been designed to satisfy the requirements of process engineering. here are three major differences to a PROFIBUS-DP system: PROFIBUS-PA supports the use of devices in explosion hazardous areas. he devices can be powered over the bus cable. he data are transferred via the IEC physical layer, which allows great freedom in the selection of the bus topology. he most important technical data are listed in able 3.1. Depending upon the application, the participants on a PROFIBUS-PA segment might be actuators, sensors and a segment coupler or link. Endress+Hauser offers PROFIBUS- PA instrumentation for the most important process variables, i.e. analysis, flow, level, pressure and temperature. Metso offers Profibus-PA valve controller, consistency transmitters and analysators. A complete list is to be found in Chapter 10. able 3.1 echnical data PROFIBUS-PA Standard EN , Part 4 Support PROFIBUS User Organisation (PNO) (PNO) Physical layer IEC Max. length 1900 m: standard und intrinsically safe applications of category ib 1000 m: intrinsically safe applications of category ia Participants Max. 10 in hazardous areas (EEx ia) max. 24 in hazardous areas (EEx ib) max. 32 in safe areas ransmission rate kbit/s Bus access method Master-slave 16 Metso Endress+Hauser

19 3.2 Segment couplers and links Class 1 master Class 2 master PROFIBUS-DP segment coupler link segment coupler JB junction box PROFIBUS-PA Fig. 3.2 Integration of a PROFIBUS-PA segment into a PROFIBUS-DP system using a segment coupler or link. PROFIBUS-PA is always used in conjunction with a supervisory PROFIBUS-DP control system. Since the protocols, physical layer and transmission rates of PROFIBUS-DP and PROFIBUS-PA are different, see ables 2.1 and 3.1, the PROFIBUS-PA segment is connected to the PROFIBUS-DP system via a segment coupler or link. A segment coupler comprises a signal coupler and bus power unit. Normally, it supports only one transmission rate on the PROFIBUS-DP side. he transmission rate for PROFIBUS-PA is fixed at kbit/s. Segment coupler hree types of segment couplers have been specified according to the type of protection required. Segment coupler ype A ype B ype C ype of protection EEx [ia/ib] IIC EEx [ib] IIB None Supply voltage 13.5 V 13.5 V 24 V Max. power 1.8 W 3.9 W 9.1 W Max. supply current 110 ma 280 ma 400 ma No. of devices approx. 10 approx. 20 max. 32 able 3.2 Segment couplers defined in standard Example of segment couplers available today. Manufacturer ype of protection Supply current Voltage DP baudrate Siemens: 6ES AD00 0XA0 EEx [ia] IIC 100 ma 12.5 V DC kbit/s Siemens: 6ES AC00 0XA0 Standard 400 ma 19.0 V DC kbit/s P+F (E+H): KFD2-BR-EX1.2PA.93 EEx [ia] IIC 110 ma 13.0 V DC kbit/s P+F (E+H): KFD2-BR-1PA.93 Standard 380 ma 25.0 V DC kbit/s A link comprises an intelligent interface and one or more segment couplers, whereby the couplers may exhibit different types of protection. Normally, a range of transmission rates are supported on the PROFIBUS-DP side. he transmission rate for PROFIBUS-PA is fixed at kbit/s. able 3.3 Segment couplers on the market Links Metso Endress+Hauser 17

20 3.3 opology he field devices on the PROFIBUS-PA segment communicate with a master on the PROFIBUS-DP system. he bus is designed according to the rules for PROFIBUS-DP up to the segment coupler or link, see Chapter 2.2. Within the PROFIBUS-PA segment, practically all topologies are permissible, see Fig Cable PROFIBUS PA defines a two-core cable as transmission medium. An informative annex to IEC lists the characteristics of four cable types that can be used as transmission medium. Cable types A and B are to be preferred for new installations. hey offer the greatest security for data transmission. In the case of cable type B, several fieldbuses (with the same type of protection) can be operated with one cable. Other current-bearing circuits in the same cable are not permitted. Cables C and D are intended only for retrofit applications, i.e. when existing cabling is to be used. hey are not suitable for use in explosion hazardous areas. Problems with the communication are also to be expected if the cables are routed through plant with heavy electromagnetic interference, e.g. near frequency converters. able 3.4 lists the technical data of each cable type: ype A ype B ype C yp D able 3.4 Cable types according to IEC , Annex C Cable contruction twisted pairs, shielded one or more twisted pairs, common shield Several twisted pairs, unshielded Several untwisted pairs, unshielded Core cross-section 0.8 mm 2 AWG mm 2 AWG mm 2 AWG mm 2 AWG 16 Loop resistance (DC) 44 Ω/km 112 Ω/km 254 Ω/km 40 Ω/km Characteristic impedance 100 Ω ± 20 % 100 Ω ± 30 % at khz Attenuation constant at 3 db/km 5 db/km 8 db/km 8 db/km 39 khz Capacitive unsymmetry 2 nf/km 2 nf/km Envelope delay distortion 1.7 µs/km ( khz) Degree of coverage of 90 % shielding Max. bus length (including spurs) 1900 m 1200 m 400 m 200 m Cable for intrinsically safe applications as per the FISCO model must also satisfy the following additional requirements: EEx ia/ib IIC EEx ib IIB able 3.5 Safety limits for the bus cable Loop resistance (DC) Ω/km Ω/km Specific inductance mh/km mh/km Specific capacitance nf/km nf/km Max. spur length 30 m 30 m Max. bus length 1000 m 1900 m Suitable cable is offered by a number of manufacturers, see Chapter Metso Endress+Hauser

21 A PNK Sk SiK (Ex i) ermination at JB possible if spurs do not exceeed 30 m JB SG (Ex i) n 4 B PNK Sk SiK (Ex i) SG (Ex i) n C PNK Sk SiK (Ex i) SG (Ex i) JB 5 6 n D PNK Sk SiK (Ex i) SG (Ex i) R+ +JB 5 R+ 6 n 7 Fig. 3.3 Bus topologies A ree B Bus C Bus + tree D Bus + tree + extension PNC: process near component SiK: Signal coupler SG: Power supply : erminator JB: Junction box R: Repeater 1...n: Field devices Sk: Segment coupler Metso Endress+Hauser 19

22 Structure he following points should be noted when designing the bus: he maximum permissible length is dependent upon the type of cable used. For cable type definitions, see able 3.4: ype A ype B ype C ype D 1900 m 1200 m 400 m 200 m For systems that are to be realised according to the FISCO model in type of protection EEx ia, the maximum bus length is 1000 m. A maximum of 32 participants are allowed in safe applications and max. 10 participants in explosion hazardous areas (EEx ia IIC). he actual number of participants must be determined during the planning of the bus, see Chapter 4. A terminator is required at each end of the segment. For PROFIBUS-PA the terminator comprises an RC combination (ohmic load 100 Ω + 1 µf). he bus length can be increased by using a repeater. Max. three repeaters are allowable between a participant and the master. Spurs he cable between the -box and field device is called a spur. Spurs longer than 1 m are counted in the total cable length. he length of the individual spurs in safe areas is dependent upon the number of participants: Participants Max. length per spur 120 m 90 m 60 m 30 m 1 m According to the FISCO model, the spurs in intrinsically safe applications may not exceed 30 m in length. A maximum of 4 field devices may be connected to a spur. 20 Metso Endress+Hauser

23 3.4 Bus access method PROFIBUS-PA uses the central master/slave method to regulate bus access. he process near component, e.g. a PLC, is a Class 1 master that is installed in the PROFIBUS-DP system. he field devices are configured from a PROFIBUS-PA Class 2 master, e.g. Commuwin II. he field devices on the PROFIBUS-PA segment are the slaves. he access to the field devices depends upon the DP/PA interface that has been installed. Segment couplers are transparent as far as the PROFIBUS-DP master is concerned, so that they are not mapped in the PLC. hey simply convert the signals and power the PROFIBUS-PA segment. he do not need to be configured nor are they assigned an address. Segment coupler he field devices in the PROFIBUS-PA segment are each assigned a PROFIBUS-DP address and behave as PROFIBUS-DP slaves. A slave may be assigned to only one Class 1 master. A master communicates directly with its slaves. A Class 1 master, e.g. the PLC, uses the cyclic polling services to fetch the data provided by the field devices. A Class 2 master, e.g. Commuwin II transmits and receives field device data by using the acyclic services. Class 1 master Class 2 master e.g. Commuwin II PROFIBUS-DP cyclic data exchange Segment coupler SiK acyclic data exchange PROFIBUS-PA field devices as DP-slaves BA198Y20 Fig. 3.4 Data exchange via segment coupler Metso Endress+Hauser 21

24 Links A link is recognised by the DP-master and is a participant in the PROFIBUS-DP system. It is assigned a PROFIBUS-DP address and thus becomes opaque to the master. he field devices on the PROFIBUS-PA side can no longer be directly polled using the cyclic services. Instead, the link collects the device data in a buffer, which can be read cyclically by a Class 1 master. Hence a link must be mapped in the PLC. On the PROFIBUS-PA side, the link acts as the bus master. It polls the field device data cyclically and stores them in a buffer. Every field device is assigned a PROFIBUS-PA address that is unique for the link, but not for other PROFIBUS-PA segments. When the link is accessed by a Class 2 master with the acyclic services it is quasitransparent. he desired field device can be accessed by specifying the link address (DP address) and the device address (PA address). Class 1 master Class 2 master e.g. Commuwin II PROFIBUS-DP Cyclic data exchange with Class 1 master using the master-slave method DP- Slave PA- Master Segment coupler Acyclic data exchange with Class 2 master using the master-slave method Cyclic data exchange with PA master using the master-slave method Fig. 3.5 Data exchange via a link PROFIBUS-PA BA198Y21 22 Metso Endress+Hauser

25 3.5 Network configuration Data exchange on the PROFIBUS-PA segment is handled by the IEC interface. he cyclic and acyclic polling services are used to transmit data. Since the PROFIBUS- PA standard offers the possibility of interconnecting devices from different vendors, a profile set has been defined that contains standardised device parameters and functions. Data ransmission Mandatory parameters:every device must provide these parameters. hese are parameters, with which the basic parameters of the device can be read or configured. Application parameters:these are optional parameters. hese parameters allow a calibration and, e.g., additional functions such as a linearisation to be performed. In view of the fact that these functions are dependent upon the measured variable, there are several profile sets, e.g. for level, pressure, flow, actuator etc.. he parameters can be accessed acyclically and require a Class 2 master, e.g. Commuwin II, if they are to be read or modified. Cyclic data exchanged is handled by standard telegrams. he permissible telegram length depends upon the master used: at the moment, masters are available that transmit 122 or 244 bytes, see Chapter 6, able 6.3. he majority of PROFIBUS-PA devices transmit measured value and status in 5 bytes, see table 6.1 on page 51. An instrument with several measured values transmits correspondingly more bytes. In the case of the flowmeter Promass 63, for example, a cyclic telegram of 51 bytes is transmitted at maximum configuration, see Chapter 2.4. In the case of the NAMUR/PROFIBUS-PA interface FXA 164, which allows the connection of up to four limit switches, the limit signals are transmitted in 2 bytes per channel. Byte 1 contains the signal condition, byte 2 the status. Depending upon the configuration, up to 8 bytes may be transmitted. In order to integrate the field devices into the bus system, the PROFIBUS-DP system requires a description of the device parameters such as output data, input data, data format, data length and the transmission rates supported. hese data are contained in the device database file (the so-called GSD file), which is required by the PROFIBUS- DP master during the commissioning of the communication system. In addition, device bitmaps are required, which appear as icons in the network tree. Further information on device database files is to be found in Chapter 6.1. A prerequisite for communication on the bus is the correct addressing of the participants. Every device on the PROFIBUS-PA segment is assigned a unique address between 0 and 125. he addressing is dependent upon the type of interface used (segment coupler or link) and is set by DIP switches, via on-site operating elements or by software. he addressing procedure is described in detail in Chapter 5. he transmission rate on a PROFIBUS-PA segment is fixed at kbit/s. In addition to the transmission rate, all active participants on the bus must operate with the same bus parameters. For the operating and display program Commuwin II, the bus parameters can be set by using the DPV1 server, see Chapter 6.5) he program can be started from the icon in the program group Commuwin II. Device database Bus address ransmission rate Bus parameters Metso Endress+Hauser 23

26 3.6 Applications in hazardous areas he explosion protection concept for the PROFIBUS-PA fieldbus is based on the type of protection "intrinsic safety i". In contrast to other types of explosion protection, intrinsic safety is not confined to the individual unit, but extends over the entire electrical circuit. All circuits connected to the PROFIBUS-PA fieldbus must be realised with type of protection "intrinsic safety", i.e. all devices and terminators that are installed in hazardous areas as well as all associated electrical apparatus (e.g. PA links or segment couplers) must be approved for the corresponding atmospheres FISCO model In order to reduce the proof of intrinsic safety of the fieldbus system, comprising different devices from different vendors, to a justifiable level, the German PB and various equipment manufacturers developed the FISCO model (Fieldbus Intrinsically Safe COncept). he basic idea is that only one device supplies power to a particular segment. he model determines the boundary conditions. he field devices are divided into those that draw their power from the bus itself, and those that must be powered locally. In addition to the type of protection "intrinsic safety", the latter devices, which require more energy, must also exhibit a further type of protection. he auxiliary energy required by the segment coupler and the locally powered devices is galvanically isolated from the intrinsically safe circuits. As is the case for all intrinsic circuits, special precautions must be observed when installing the bus. he aim is to maintain the separation between the intrinsically safe and all other circuits. Grounding Category Explosion group he intrinsically safe fieldbus circuit is operated earth-free, which does not preclude that individual sensor circuits can be connected to ground. If a overvoltage protector is installed before the device, it must be bonded to the plant grounding system in accordance with the instructions in the certificate or device manual. Particular attention must be paid to the grounding of the conducting cable screening because if it is to be earthed at several positions, a high integrity plant grounding system must be present. he category of the intrinsically safe field bus is determined by the circuit with the worst rating, i.e. if the fieldbus circuit of one device has the type of protection EEx ib, then the whole fieldbus falls in the category ib. Devices that must be connected to a circuit with type of protection EEx ia (requirements as per certificate) may not be operated on field bus circuits with type of protection ib. Only circuits that are connected directly to thefieldbus must be considered here. Devices that are approved for different explosion groups (IIC, IIB or IIA) can be operated on the same segment. he permissible explosive atmosphere allowed at a particular device is determined by the type of protection of that device as well as the explosion group for which the segment coupler is approved. All devices and terminators that are installed in hazardous areas as well as all associated electrical apparatus (e.g. PA links or segment couplers) must be approved for the corresponding atmospheres, e.g. PB, BVS, FMRC, CSA etc.. 24 Metso Endress+Hauser

27 he bus system is powered by a segment coupler. he field devices function as current sinks and draw a direct current of about 10 ma from the bus cable (some participants require more). his current supplies the energy necessary for operation. If a field device transmits data, it does so by modulating the current by ±9 ma. Operating principle When it is transmitting data, the fieldbus acts as an ohmic resistance. Since the device does not output power, the intrinsic safety of a bus segment is largely determined by the current and voltage limitations placed on the bus power supply. field device current 25 ma 19 ma max.current fault current In order that a field device does not block the bus should it fail, its maximum current consumption is limited by the so-called fault disconnection electronics (FDE). his current must be considered when the segment is planned. 10 ma 1 ma basic current t Fig. 3.6 Function of a PROFIBUS-PA device An important requirement for participants on a PROFIBUS-PA segment, is that a defective device may not detrimentally effect the functioning of the system. he fault disconnection electronics ensure that high current consumption is not possible. An electronic circuit detects the rise in the basis current above the specified manufacturer's value and either limits the current consumption or isolates the participant from the bus. he increase in basic current above the normal value in the event of a fault is designated the fault current. Due to the FISCO model, the following points only must be observed when a PROFIBUS-PA segment is planned for use in a hazardous area. Fault disconnection electronics PROFIBUS-PA segments he maximum permissible bus length is dependent upon the type of segment coupler used, the topology of the bus, the bus power and the specific resistance of the cable. For EEx ia IIC, the maximum length is 1000 m. If intrinsically safe circuits of category ia and ib are connected to the same segment, the type of protection of the entire segment is ib. It may be necessary to distribute the field devices on two separate segments, should a circuit of category ia be mandatory for a device or component. Furthermore, the following applies generally he number of participants that may be connected to a segment is determined by the highest FDE current, the sum of the basic currents and the power that can be supplied by the segment coupler. he following information is required for proof of intrinsic safety: Proof of intrinsic safety he total cable length including all spurs greater than 1 m must ber less than 1000 m (EEx ia IIC) No spur longer than 30 m All participants conform to the FISCO model. For every participant I Segment coupler > I Device U Segment coupler > U Device P Segment coupler > P Device More information on the planning of a PROFIBUS-PA segment is to be found in Chapter 4. Metso Endress+Hauser 25

28 4 Planning Various aspects must be taken into consideration when a PROFIBUS-PA segment is planned. Since the importance of each aspect varies from system to system, it is recommended that the following sections are worked through one after the other. If at some point it becomes obvious that a concept cannot be realised, then start the whole procedure again from the beginning with a modified concept. he chapter is structured as follows: Selection of the segment coupler Cable type and length Calculation of current consumption Voltage at last device Calculation examples for bus design Data quantity Cycle times Addressing Example calculations for addressing and cycle times 4.1 Selection of the segment coupler he first step in planning a PROFIBUS-PA system is the selection of the segment coupler according to the criteria laid down in Chapter 3.6. able 4.1 summerises these: Zone/Explosion group Segment coupler Remarks able 4.1 Selection of the segment coupler according to the type of protection and the explosion group of the measured media. Zone 0 [EEx ia] IIx Devices that are in installed in Zone 0 must be operated in a segment with type of protection "Ex ia".î All circuits connected to this segment must be certified for type of protection "Ex ia". Zone 1 [EEx ia] IIx [EEx ib] IIx Devices that are in installed in Zone 1 must be operated in a segment with type of protection "Ex ia" or "Ex ib". All circuits connected to this segment must be certified for type of protection "Ex ia" or "Ex ib". Explosion group IIC [EEx ia] IIC If measurements and control are made in a medium of explosion group IIC, the devices concerned as well as the segment coupler must be certified for explosion group IIC. Explosion group IIB [EEx ia] IIC [EEx ib] IIB For media of explosion group IIB, both the devices and the segment coupler can be certified for both group IIC or IIB. Non-Ex Non-Ex Devices that are operated on a non-ex segment may not be installed in an explosion hazardous area. Segment coupler Example of segment couplers available today: Manufacturer Designation ype of protection Current output Voltage able 4.2 Examples of segment couplers together with specifications Siemens 6ES AD00 0XA0 [EEx ia] IIC 100 ma 12.5 VDC Siemens 6ES AC00 0XA0 Standard 400 ma 19.0 VDC P+F KFD2-BR-EX1.2PA.93 [EEx ia] IIC 100 ma 13.0 VDC P+F KFD2-BR-1PA.93 Standard 400 ma 25.0 VDC 26 Metso Endress+Hauser

29 4.2 Cable type and length he bus length is dependent upon the type of protection of the segment and the specification of the cable. In order that the basic requirements for transmission on the IEC physical layer are fulfilled and that the inductance and capacitance of the cable can be neglected, the bus length and loop resistance are limited. able 4.2 lists the PROFIBUS-PA specifications. Power supply ype A ype B ype C Application EEx [ia/ib] IIC EEx [ib] IIB Standard Supply voltage* 13.5 V 13.5 V 24 V Max. power* 1.8 W 4.2 W 9.1 W Max. current consumption* 110 ma 280 ma 400 ma Max. loop resistance 40 Ω 16 Ω 39 Ω Max. bus segment length 1000 m (EEx ia) 1900 m 1900 m Max. spur length 30 m 30 m see able 4.4 *see also the technical data supplied by the manufacturer able 4.3 Standardised power supplies with max. loop resistance and bus length for various applications he bus length is the sum of the length of the trunk cable plus all spurs. If a repeater is used, then the max. permissible length is doubled. he spurs are subject to the following limitations: Bus length Spurs Spurs longer than 30 m are not permissible in explosion hazardous areas. For non-hazardous applications, the maximum length of a spur is dependent upon the number of field devices, see able 4.4. Spurs which are shorter than 1 m are treated as connection boxes and are not included in the calculation of the total bus length, provided that they do not together exceed 8 m for a 400 m bus or 2 % of the total length for a longer bus. No. of field devices Spur length 1 m 30 m 60 m 90 m 120 m able 4.4 Max. spur lengths for nonhazardous he maximum cable length for a particular cable resistance is calculated as follows, whereby the limits in able 4.4. must be observed. Max. cable length Max. cable length (km) = max. loop resistance of the segment coupler (able 4.3) specific resistivity of the cable (Ω/km) If not given, the loop resistance is (Ω/km) = 2 x (1000 ρ/a) whereby ρ = specific resistivity Ω mm 2 /m und A = core cross-section mm 2. able 4.5 list examples for the PROFIBUS-PA cable available from various manufacturers. Manufacturer Order No. Application Specific resistance Siemens 6XV1830-5BH10 Standard 44 Ω/km Siemens 6XV1830-5AH10 EEx ia/ib IIC 44 Ω/km Kerpen CEL-PE/OSCR/PVC/FRLA FB-02YS(St)Y# Standard Kerpen CEL-PE/OSCR/PVC/FRLA FB-02YS(St+C)Y# EEx ia/ib IIC Belden 3076F (used in urck products) Standard 45.4 Ω/km able 4.5 Loop resistance of various PROFIBUS-PA cables Metso Endress+Hauser 27

30 4.3 Calculation of current consumption he primary factors in determining the number of devices on a segment are the current supplied by the segment coupler and the current consumption of the field devices. For this reason, the current consumption must be calculated for every segment. As a rule of thumb for general planning: Max. 32 devices per segment are permissible in non-hazardous areas (A repeater allows more devices on the segment). Max. 10 devices are permissible in hazardous areas of category ia. For the calculation, the current supplied by the segment coupler I s, the basic current of every device IB and the fault current of every device IFDE must be known. From the electrical point of view, a segment is permissible when: I s I SEG whereby I SEG = I B + max. I FDE able 4.6 lists the basic current, the fault current and other specifications of Endress+Hauser and Metso devices. he following examples illustrate how the calculation should be made. Empty forms can be found in Appendix A. ype Application ID code ype of protection Basic current I B Fault current I FDE Auxiliary energy able 4.6 PROFIBUS-PA data of E+H and Metso devices Cerabar S Pressure 1501 EEx ia IIC 11 ma 0 ma from bus Deltabar S Differential 1504 EEx ia IIC 11 ma 0 ma from bus pressure Deltapilot S Level 1503 EEx ia IIC 11 ma 0 ma from bus Micropilot Level 150A EEx ia IIC 12 ma 0 ma from bus Mycom II ph/redox 1508 EEx em [ia/ib] IIC* 11 ma 0 ma local Conductivity 1509 EEx em [ia/ib] IIC* 11 ma 0 ma local (cond). Conductivity 150B EEx em [ia/ib] IIC* 11 ma 0 ma local (ind) Promag 33 Flow 1505 EEx de [ib/ia] IIC* 12 ma 0 ma local Promag ma 0 ma local Promass 63 Flow 1506 EEx de [ib/ia] IIC* 12 ma 0 ma local EEx d [ib/ia] IIC* Prowirl 77 Flow 1510 EEx ia IIC 11 ma 0 ma from bus Prosonic Level 1502 EEx ia IIC 13 ma 0 ma from bus FMU 232 EEx d # 17 ma 0 ma MD 834 emperature 1507 EEx ia IIC 13 ma 0 ma from bus Mypro Conductivity 150C EEx ia IIC 11 ma 0 ma from bus ph/redox 150D EEx ia IIC 11 ma 0 ma from bus Liquisys Conductivity 1515 None 11 ma 0 ma local ph ma 0 ma urbidity ma 0 ma Oxygen ma 0 ma Chlorine ma 0 ma FXA 164 Level limit 1514 EEx ia IIC 30 ma 0 ma from bus RID 261 Display EEx ia IIC 11 ma 0 ma from bus ND800PA Positioner 052d EEx ia IIC/5/6 23,45 ma 3,55 ma from bus 28 Metso Endress+Hauser

31 4.4 Voltage at last device he resistance of the cable causes a voltage drop on the segment that is greatest at the device which is farthest from the segment coupler. It must be checked whether an operating voltage of 9 V (for FEB 20 in Zone V) is present at this device. Ohm's law is used: U B = U S (I SEG x R SEG ) whereby: U B = Voltage at last device U S = Output voltage of the segment coupler (manufacturer's data) I SEG = Current consumed on the segment (as calculated in Section 4.2) R SEG = Cable resistance = bus length x specific resistivity 4.5 Calculation examples for bus design Specimen calculation for a bus operating in a safe area with the architecture shown in Fig Standard segment coupler: Siemens, I s = 400 ma, U s = 19 V. Cable: Siemens, 44 Ω/km Example 1, non-hazardous application runk cable 60 m Standard segment coupler: U s =19V I s = 400 ma 7m 5m 15 m 20 m 20 m 7m 7m 5m 15 m 20 m 20 m 1 2 U B = V spur Fig. 4.1 Example 1: Bus installed in non-hazardous area Max. loop resistance, standard segment coupler (see able 4.2) Specific resistance of cable (e.g. Siemens) Max. length (m)= 1000 x loop resistance/specific resistance 1000 x (39 Ω/44 39 Ω) = 39 Ω 44 Ω/km 886 m Cable length Length of trunk cable 60 m otal length of spurs 141 m otal length of cable (= trunk cable + spurs) L SEG 201 m otal length of cable 201 m < Max. length 886 m OK! Metso Endress+Hauser 29

32 Current consumption No. Device Manufacturer ag Basic current Fault current 1 Promass 63 Endress+Hauser FIC ma 0 ma 2 ND800PA Metso VIC ma 3 Deltapilot S Endress+Hauser LIC ma 0 ma 4 MD 834 Endress+Hauser IC ma 0 ma 5 Promass 63 Endress+Hauser FIC ma 0 ma 6 ND800PA Metso VIC ,45 3.,5 ma 7 Promass 63 Endress+Hauser FIC ma 0 ma 8 ND800PA Metso VIC ma 9 Deltapilot S Endress+Hauser LIC ma 0 ma 10 MD 834 Endress+Hauser IC ma 0 ma 11 Promass 63 Endress+Hauser FIC ma 0 ma 12 ND800PA Metso VIC ma Max. fault current (max. I FDE ) 3.55 ma Current consumption I SEG = ΣI B + max. I FDE ma Output current of segment coupler Is 400 ma I s SIB + max. I FDE? yes OK! Voltage at last device Conclusion Output voltage of segment coupler US (manufacturer s data) V Specific resistance of cable R K (e.g. Siemens) 44 Ω/km otal length of cable L SEG 201 m Resistance of cable R SEG = L SEG x R K Ω Current consumption of segment I SEG 193,45 ma Voltage drop U A = I SEG x R SEG 1.71 Voltage at last device U B = U S - U A U B 9 V?** OK! Result of the calculations: Cable length: OK Current consumption: OK Voltage at last device: OK From the point of view of the architecture, the segment in Example 1 can be operated with a standard segment coupler with an output current of 400 ma. In this case, two additional tanks with identical instrumentation could be operated on the same segment. 30 Metso Endress+Hauser

33 In Examples 2 and 3, the PROFIBUS-PA segment is to operate in an explosion hazardous area. In accordance with the FISCO model, the devices are operated on two separate segments with type of protection EEx ia for Zone 0 and EEx ib for Zone 1. Calculations are made for both segments. Specimen calculation for a bus operating in a hazardous area Zone 0 with the architecture shown in Fig Segment coupler [EEx ia] IIC: Siemens, I s = 100 ma, U s = 13 V. Cable: Siemens 44 Ω/km, max. bus length = 1000 m Example 2, EEx ia Segment coupler [EEx ia] IIC I s = 100 ma U s =13V U B = V 5m trunk cable 50 m 5m EEx ib EEx ia m 7 8 Zone 0 Zone 0 15 m Zone 1 Zone 1 spur Fig. 4.2 Example 2: Calculation of the segment EEx ia. Bus installed with routing to Zone 0 (EEx ia) and Zone 1 (EEx ib) Max. loop resistance, EEx ia (see able 4.2) Specific resistance of cable (e.g. Siemens) Max. length (m)= 1000 x loop resistance/specific resistance 1000 x (40 Ω/44 Ω) = 40 Ω 44 Ω/km 909 m Cable length: Length of trunk cable otal length of spurs otal length of cable (= trunk cable + spurs) L SEG 50 m 40 m 90 m otal length of cable 90 m < Max. length 909 m OK! No. Device Manufacturer ag Basic current Fault current 3 Deltapilot S Endress+Hauser LIC ma 0 ma 4 MD 834 Endress+Hauser IC ma 0 ma 9 Deltapilot S Endress+Hauser LIC ma 0 ma 10 MD 834 Endress+Hauser IC ma 0 ma Max. fault current (max. IFDE) 0 ma Current consumption Current consumption I SEG = SIB + max. I FDE 48 ma Output current of segment coupler I s 100 ma I s SI B + max. I FDE? ja OK! Metso Endress+Hauser 31

34 Voltage at last device Output voltage of segment coupler U S (manufacturer s data) Specific resistance of cable RK (e.g. Siemens) 44 Ω/km otal length of cable L SEG 90 m Resistance of cable R SEG = L SEG x R K 3.96 Ω Current consumption of segment I SEG 48 ma Voltage drop U A = I SEG x R SEG Voltage at last device U B = U S - U A U B 9 V?* V 0.19 V V OK! Conclusion Example 3, EEx ib Result of the calculations: Cable length: OK Current consumption OK Voltage at last device OK From the point of view of the architecture, the segment in example 2 can be operated with an EEx ia segment coupler with an output current of 100 ma. Specimen calculation for a bus operating in a hazardous area Zone 1with the architecture shown in Fig Segment coupler [EEx ia/ib] IIC: P+F, I s = 100 ma, U s = 13 V. Cable: Siemens, 44 Ω/km Segment coupler [Ex ia/ib] IIC I s = 100 ma U s =13V runk cable 60 m EEx ib EEx ia. 7m 7m 7m 7m 1 2 U B = 12,22 V 7 8 Zone 0 Zone 0 Fig. 4.3 Example 3: Calculation of the segment EEx ib, Bus installed with routing to Zone 0 (EEx ia) and Zone 1 (EEx ib) m 20 m spur 5 6 Zone 1 Zone m 20 m Cable length: Max. loop resistance, EEx ib (see able 4.2) Specific resistance of cable (e.g. Siemens) Max. length (m)= 1000 x loop resistance/specific resistance 1000 x ( Ω/ Ω) = 16 Ω Ω/km 363 m Length of trunk cable 60 m otal length of spurs 108 m otal length of cable (= trunk cable + spurs) L SEG 168 m otal length of cable 168 m < Max. length 363 m OK! 32 Metso Endress+Hauser

35 No. Device Manufacturer Measuring point Basic current Fault current 1 Promass 63 Endress+Hauser FIC ma 0 ma 2 Positioner VIC ma 4 ma 5 Promass 63 Endress+Hauser FIC ma 0 ma 6 Positioner VIC ma 6 ma 7 Promass 63 Endress+Hauser FIC ma 0 ma 8 Positioner VIC ma 4 ma 11 Promass 63 Endress+Hauser FIC ma 0 ma 12 Positioner VIC ma 4 ma Max. fault current (max. I FDE ) 6 ma Current consumption Current consumption I SEG = SI B + max. I FDE 106 ma Output current of segment coupler Is (EEx ia IIB) 100 ma I s ΣI B + max. I FDE? no Impossible! Speisestrom eines Segmentkopplers I s (EEx ib IIB) 280 ma I s SI B + max. I FDE? yes OK! Output voltage of segment coupler US (manurer s data) 13 V Specific resistance of cable R K (e.g. Siemens) 44 Ω/km otal length of cable L SEG 168 m Resistance of cable R SEG = L SEG x R K 7.39 Ω Current consumption of segment I SEG 106 ma Voltage drop U A = I SEG x R SEG 0.78 V Voltage at last device U B = U S - U A V U B 9 V?* OK! Result of the calculations: Voltage at last device Conclusion Cable length: Current consumption Voltage at last device OK EEx ia not permissible, EEx ib OK OK he result for a segment with type of protection EEx ib and a segment coupler EEx ia IIC is negative. A segment coupler with type of protection EEx ib IIB would be permissible but at the moment there is none on the market. wo possible alternatives are shown in Fig. 4.4: Version A: two segments with type of protections EEx ib are routed to one tank each. In this case, the current consumption is reduced to 56 ma. A segment coupler with type of protection EEx ia IIC is adequate for this requirement. Version B: only circuits with type of protection EEx ia are connected to the bus. he plant can then be equipped with two segments with type of protection EEx ia. he current consumption per segment is 80 ma. Metso Endress+Hauser 33

36 Version A Segment coupler. 3x [EEx ia] IIC EEx ib EEx ib EEx ia. 1 2 Zone Zone Zone 1 Zone 1 Version B Segment coupler. 2x [EEx ia] IIC EEx ia. EEx ia. Fig. 4.4 Example 2: Alternative architectures: 1 2 Zone Zone 0 Version A two segments with degree of protection EEx ib IIC Version B two segments with degree of protection EEx ia IIC : erminator Zone Zone Metso Endress+Hauser

37 4.6 Data quantity If the participants communicate directly with the PROFIBUS-DP master through a segment coupler, then the amount of data exchanged sets no limits to the design of the PROFIBUS-DP segment. If a link is used as interface to the PROFIBUS-DP system, however, the amount of data that can be stored in the I/O buffer is limited. he maximum telegram length that can be handled by the PLC must also be taken into consideration. able 4.7 summarises the measured values, amount of data and cycle times associated with Endress+Hauser and Metso devices. able 6.3 in Chapter 6.4 lists the telegram lengths of various PLCs. Specifications in bytes Amount of data bytes to PLC Link, non-hazardous area bytes per device Fig. 4.5 Example 1: Bus installed in non-hazardous area ake Example 1 in Fig 4.5: can a link be used? Example: Data quantity 4x devices deliver 4x 5 bytes = 20 bytes 4x Promass deliver 4x 6 to 51 byte = bytes 4x positioners deliver 4x 0 to 15 byte = bytes Depending upon the device configuration, from 44 bytes to 284 bytes are periodically exchanged with the PLC. In the case of a link, the data are transmitted to the PLC in a telegram. he telegram length is limited: a) by the buffer size of the link, e.g. 244 bytes, b) by the max. telegram length of the PLC, e.g. 122 bytes c) by the PROFIBUS-PA specification 244 bytes. It can seen that the use of a link is determined by the configuration of the field devices and the system components used. Should the maximum configuration be required, a link could not be used. Metso Endress+Hauser 35

38 ype Cyclic data Data amount Response time Function blocks Cerabar S Pressure 5 byte 10 ms AI, PB, B pressure Deltabar S Differential pressure 5 byte 10 ms AI, PB, B pressure Deltapilot S Level 5 byte 10 ms AI, PB, B level Micropilot Level 5 byte 10 ms AI, PB, B level Mycom II ph Wert byte 10 ms...11,3 ms AI, PB emperature Conductivity (ind.) byte 10 ms...11,3 ms AI, PB emperature Conductivity (cond.) byte 10 ms...11,3 ms AI, PB emperature Promag 33/35 Flow otalisator Control byte + 1 byte output data 5 byte byte + 1 byte output data 10 ms...11,3 ms AI, PB, B flow B totalisor Promass 63 Mass flow otalisator 1 emperature Density otalisator 2 Volumetric flow Satndard volumetric flow arget medium flow Carrier medium flow Calculated density Control 10 ms ms 8x AI, PB, B flow 2x B totalisor able 4.7 PROFIBUS-PA data of E+H and Metso devices Prowirl 77 Flow otalisator Control 5 byte...10 byte + 1 byte output data 10 ms ms AI, PB, B flow B totalisor Prosonic Level 5 byte 10 ms AI, PB, B level MD 834 emperature 5 byte 10 ms AI, PB, B temp. Mypro Conductivity, byte 10 ms ms AI, PB emperature ph value byte 10 ms ms AI, PB emperature Liquisys ph value byte 10 ms ms AI, PB emperature O2, emperature byte 10 ms ms AI, PB Cl2, emperature byte 10 ms ms AI, PB urbidity, emperature byte 10 ms ms AI, PB Conductivity byte 10 ms ms AI, PB emperature FXA 164 Level limit byte 10 ms ms DI, PB RIB 261 Display 0 byte 0 ms Listener function ND800PA SP, READBACK, POS_D, CHECKBACK byte 10 ms AO, PB, B positioner 36 Metso Endress+Hauser

39 4.7 Cycle times In addition to the amount of data, the cycle times must also be considered when the PROFIBUS-PA segment is planned. Data exchange between a PLC (a Class 1 master) and the field devices occurs automatically in a fixed, repetitive order. he cycle times determine how much time is required until the data of all the devices in the network are updated. he more complex a device is, the greater the amount of data to be exchanged and the longer the response time for the exchange between PLC and device. able 4.7 summarises the amount of data and the response times for Endress+Hauser and Metso devices. he total cycle time for the updating of network data is calculated as follows: otal cycle time = Sum of the cycle times of the field devices + internal PLC cycle time + PROFIBUS-DP transmission time Examples can be found in Section 4.9. he total cycle time of a system can be reduced considerably by the use of links. he limitation placed on the transmission rate of the PROFIBUS-DP side by a segment coupler is eliminated. Links 4.8 Addressing Every device in the bus system is assigned a unique address. Valid addresses lie in the range If the address is not set correctly, the device cannot communicate. he PLC is able to assign up to 126 addresses to individual devices. A device address may appear only once within a particular PROFIBUS-DP system. If a segment coupler is used, then the addresses assigned to the PROFIBUS-PA devices count as PROFIBUS-DP addresses. For a typical bus configuration with PLC and PC, the addresses are assigned as follows: PROFIBUS-DP network the PLC is assigned an address (Class 1 master) the PC or operating tool is assigned an address (Class 2 master) the other addresses are assigned to the field devices. If one or more links are in use, these are considered to be on the PROFIBUS-DP network. he field devices connected to link, however, form a separate PROFIBUS-PA system. In this case, the PROFIBUS-DP addresses are assigned as follows: Addressing with a link the PLC is assigned an address (Class 1 master) the PC or operating tool is assigned an address (Class 2 master) every link is assigned an address: he field devices connected to the link are assigned a unique address for the PROFIBUS-PA segment of which they are part. hey are not counted as part of the PROFIBUS-DP system. the rest of the addresses are assigned to the other field devices that are connected to transporent segment couples or directly to the PROFIBUS-DP system. On the PROFIBUS-PA side, every device is assigned an address between 3 and 126, (the addresses 0 and 1 are reserved). Address 2 is reserved for the link. hree examples for addressing are to be found in Section 4.9. Metso Endress+Hauser 37

40 4.9 Example calculations for addressing and cycle times Example 1: Siemens segment coupler Siemens segment couplers can be used by any PROFIBUS-DP master (PLC or process control system) that supports a baudrate of kbit/s. In the example, two couplers for hazardous areas and one for non-hazardous areas are used. A maximum of 126 (0-125) addresses can be given to the participants, since the segment coupler is transparent. 124 addresses are available for assignment to the field devices. he addresses 3-19 are used. he transmission rate is kbit/s. he cycle time for the following example is: (cycle time of the devices) + PLC cycle time (ca. 100 ms) = 17 x 10 ms ms = 270 ms Note! For PROFIBUS-DP alone, the DP transmission time must also be considered. Note! Segment coupler [EEx ia] IIC/IIB Non-hazardous area Device designation 6ES AD00-0XA0 6ES AC00-0XA0 max. output current 100 ma 400 ma power supply CPU 100 ms DP master address A 1 Operating tool address A 2 PROFIBUS-DP kbit/s Standard segment coupler Ex segment coupler Ex segment coupler A8 A14 A3 A9 A15 A4 A10 A16 PROFIBUS- PA A5 A6 PROFIBUS- PA A11 A12 PROFIBUS- PA A17 A18 A7 A13 A19 Fig. 4.6 Example of network for Siemens segment coupler Safe area Explosion hazardous area 38 Metso Endress+Hauser

41 he Peppert + Fuchs segment coupler can be used by any PROFIBUS-DP master (PLC or process control system). It can thus be used in all common configurations. In the example, two couplers for hazardous areas and one for non-hazardous areas are used. Example 2: Pepperl + Fuchs segment coupler A maximum of 126 (0-125) addresses can be given to the participants, since the segment coupler is transparent. 124 addresses are available for assignment to the field devices. he addresses 3-19 are used. he transmission rate is kbit/s. he cycle time for the following example is: (cycle time of the devices) + PLC cycle time (ca. 100 ms) = 17 x 10 ms ms = 270 ms Note! For PROFIBUS-DP alone, the DP transmission time must also be considered. Segment coupler [EEx ia] IIC/IIB Non-hazardous area Note! Device designation KFD2-BR-EX1.2PA93 KFD2-BR-1PA.93 max. output current 100 ma 400 ma power supply CPU 100 ms DP master address A 1 Operating tool address A 2 PROFIBUS-DP kbit/s Standard segment Ex segment coupler Ex segment coupler A8 A14 A3 A9 A15 A4 A10 A16 PROFIBUS- PA A5 A6 PROFIBUS- PA A11 A12 PROFIBUS- PA A17 A18 A7 A13 A19 Safe area Hazardous area Fig. 4.7 Network example for P+F segment Metso Endress+Hauser 39

42 Example 3: Siemens PA-link he Siemens PA-link can be used by any PROFIBUS-DP master (PLC or process control system). hree links are used in the example: two links for hazardous areas and one for non-hazardous areas. wo segment couplers for non-hazardous areas are connected to the link for non-hazardous areas. Similarly two segment couplers for hazardous areas are connected to the hazardous area link. A maximum of 126 addresses can be assigned to the participants on the PROFIBUS-DP system. A maximum of 30 addresses (address range 3-126) can be assigned in the PROFIBUS-PA segments connected to the link. he PROFIBUS-DP addresses 3-5 are used to address the links. In the PROFIBUS-PA segments, the addresses 2-11, 2-10 and 2-9 are used, whereby address 2 is reserved for the link in each case. he transmission rate may be up to 12 Mbit/s. he cycle time for the following example is: (cycle time of the devices) + cycle time per link + PLC-cycle time PROFIBUS-PA segment 1: 9 x 10 ms + 3 x 1 ms ms = 193 ms PROFIBUS-PA segment 2: 8 x 10 ms + 3 x 1 ms ms = 183 ms PROFIBUS-PA segment 3: 7 x 10 ms + 3 x 1 ms ms = 173 ms Note! For PROFIBUS-DP alone, the DP transmission time must also be considered. Note! Segment coupler [EEx ia] IIC/IIB Non-hazardous area PA Link (IM157) Device designation 6ES AD00-0XA0 6ES AC00-0XA0 6ES AC00-0XA0 max. output current 100 ma 400 ma power supply CPU 100 ms DP master addess A1 Operating tool address A2 PROFIBUS-DP...12Mbit/s A3 Standard segment Ex segment coupler Ex segment coupler A4 A5 Link Link Link PA 2 PA 2 PA 2 PA 7 PA 7 PA 3 PA 6 PA 3 PA 8 PA 3 PA 8 PA 7 PROFIBUS-PA PA 4 PA 5 PA 9 PA 10 PROFIBUS-PA PA 4 PA 5 PA 9 PROFIBUS-PA PA 4 PA 8 PA 6 PA 11 PA 6 PA 10 PA 5 PA 9 Subnetwork Subnetwork Subnetwork Fig. 4.8 Network example for Siemens link Non-hazardous area Explosion-hazardous area 40 Metso Endress+Hauser

43 5 Installation When installing a PROFIBUS-PA segment, particular attention must be paid to the wiring. he customer has two choices: -box with screw terminals Cord sets with M12 connector. In both cases, care must be taken regarding the continuity of the screening and the correct termination of the segment. PROFIBUS-DP systems are usually connected together by means of Sub-D connectors, since there are currently no special components. he correct installation of the field devices is also important. Since this is beyond the scope of these guidelines, the information should be taken from the corresponding device instructions. Finally, the address must be set. he way in which this is done has an influence on how the segment is subsequently commissioned. he chapter contains the following sections: Cabling in safe areas Example: screening in safe areas Example: screening in explosion hazardous areas ermination Overvoltage protection Installation of the devices Addressing Note! Endress+Hauser devices that are suitable for use in explosion hazardous areas are designed such that the circuit that is connected to the bus exhibits the type of protection "intrinsic safety" category ia. In contrast to loop-powered devices, four-wire devices have further types of protection. his must be taken into account when the device is installed. Since the connection compartment for the intrinsically safe circuits are designed with type of protection EEx d or EEx e, the M12 connector cannot be used for EEx d devices and only under certain conditions for EEx e devices. Note! Metso Endress+Hauser 41

44 5.1 Cabling in safe areas Screened cable must always be used, see Chapter 3.2. In order to obtain the optimal effectiveness, the screening should be connected as often as possible to ground. he external ground terminal on the transmitter must be connected to ground. he screening must be grounded at each end of the cable. In the event of large differences in potential between the individual grounding points, only on point on the screening should be connected to the ground. All other screening ends are connected to ground via a capacitor that is suitable for HF applications. (Recommended: ceramic capacitor 10 nf/250 V~) -box (E+H Order Nos.) Aluminium housing IP 67 with 4-pin connector with special Pg9 (Iris spring) switchable bus terminator with standard Pg, switchable bus terminator, internal grounding capacitor 10 nf (for capacitive grounding) Depending upon the -box, the cable screening is grounded via a 10 nf capacitor or a special Pg cable gland. If necessary, the capacitor can be replaced by a wire jumper. plant ground next -box 100 B S A Bus cable 1µF Bus cable A S B connector Fig. 5.1 Optimal EMC connection when voltage differences between the grounding points are small cable gland with iris spring and/or connected screening PROFIBUS-PA device via M12 connector jumper bus terminator ON bus terminator OFF Screening the spur/ -box Use cable glands with good electromagnetic compatibility, if possible with all-round contacting of the cable screening (iris spring). A prerequisite is small potential differences, if necessary with equipotential bonding. he continuity of the PA cable screening between tapping points must be ensured. he connection to the screening must be kept as short as possible. Ideally, cable glands with iris spring should be used to connect the cable screening to -boxes. he iris spring within the gland connects the screening to the -box housing. he woven screening lies under the iris spring. When the gland is tighten, the spring is squeezed tight onto the screening, producing good electrical contact between the screening and the metal housing. A -box is to be seen as part of the screening (Faraday cage). his applies in particular drop-line boxes, when they are connected to a PA device via plug and cable. In such cases, a metal plug must be used, in which the cable screening is in direct contact with the plug housing, e.g. a cord set. 42 Metso Endress+Hauser

45 5.2 Example: screening in safe areas Note! hese suggestions may deviate from existing standards (IEC ) and guidelines, but produce optimal installation from an EMC point of view. Optimal installation when an equipotential bonding system exists Note! Example 1 When the device is not connected directly to the -box or junction box, use a cord set ➀ with M12 connector. -box -box power supply/ segment coupler ground connection as short as possible field device cable gland with iris spring plug with ground connection field device Plant grounding system (German practice shown here) Fig. 5.2 Optimal installation when an equipotential bonding system exists Isolated installation when no additional grounding is allowed or when the potential differences between the grounding points are too great (the customer's grounding concept must be observed). Example 2 he segment coupler is the preferred point to fully connect the screening (i.e. not via a capacitor) When the device is not connected directly to the -box or junction box, use a cord set ➀ with M12 connector. -box -box power supply/ segment coupler standard Pg 9 capacitors: max. 10 nf/250 V~ ➀ field device field device Fig. 5.3 Alternative installation for isolated version Metso Endress+Hauser 43

46 5.3 Example: screening in explosion hazardous areas he examples which follow reflectgerman practice - when adapting them for international use, please observe your national regulations. -boxes and junction boxes must be certified for use in hazardous areas (light blue colour), type of protection EEx ia. E+H order number: e.g Example 1 Common grounding of all devices When the device is not connected directly to the -box or junction box, use a cord set ➀ with M12 connector. he connection between the screening/housing is not routed into the -box ➁ and must be pulled in afterwards. Non-hardardous area -box -box terminator E+H Order No power supply/ segment coupler standard Pg 9 2 ➀ field device field device Fig. 5.4 Common grounding of all devices plant grounding system (German practice shown here) Example 2 Separate grounding of the devices between safe and hazardous areas. When the device is not connected directly to the -box or junction box, use a cord set ➀ with M12 connector. he connection between the screening/housing is not routed into the -box ➁ and must be pulled in afterwards. Use a small capacitor (e.g. 1 nf/1500 V dielectric strength, ceramic) ➂. he total capacitance connected to the screening must not exceed 10 nf. Non-hardardous area -box -box terminator E+H Order No power supply/ segment coupler screening isolated from housing standard Pg 9 2 ➀ field device field device Fig. 5.5 Separate grounding of the devices between safe and hazardous areas. plant grounding system (German practice shown here) 44 Metso Endress+Hauser

47 5.4 ermination he start and end of every PROFIBUS-PA segment must be fitted with a bus terminator. For non-hazardous areas, some -boxes have an integrated terminating element that can be switched in when required. If this is not the case, a separate terminator must be used. he segment coupler at the beginning of the segment has a built in terminator. he terminator in the -box at the end of the segment must be switched in, or a separate terminator must be used. -boxes with switchable terminators may not be used in explosion hazardous areas. he terminator requires the corresponding FISCO approval and is a separate unit. For a segment with a tree architecture, the bus ends at the device that is the furthest from the segment coupler. For a junction box, the termination can be made at the box, provided that none of the connected spurs exceeds 30 m in length. If the bus is extended by the use of a repeater, then the extension must also be terminated at both ends. he beginning and end of the PROFIBUS-DP segment must also be terminated, see Chapter 2. he terminating resistors are already built into most of the connectors on the market and must only be switched in. 5.5 Overvoltage protection Depending upon the application, the PROFIBUS-PA segment can also be protected against overvoltages. An overvoltage protector is installed immediately after the segment coupler. An overvoltage protector is installed immediately before every device (between the device and the -box). In the case of hazardous applications, each overvoltage protector must have the corresponding approval. he manufacturer's instructions are to be observed when installing. he overvoltage protectors HAW 560 (standard) and HAW 562 Z (hazardous applications) are available from Endress+Hauser or direct from the manufacturer (Dehn und Söhne, Neumarkt, Germany) Segment coupler field device Overvoltage protection Fig. 5.6 PROFIBUS-PA overvoltage protection system Metso Endress+Hauser 45

48 5.6 Installation of the devices he devices must be installed in accordance with the following operating manuals. ID Code Device Operating instructions 1501 Cerabar S BA 168P/00/de 1502 Prosonic BA 166F/00/de 1503 Deltapilot S BA 164F/00/de 1504 Deltabar S BA 167P/00/de 1505 Promag 33/35 BA 029D/06/de 1506 Promass 63 BA 033D/06/de 1507 MD 834 BA 090R/09/de 1508 Mycom II ph BA 143C/07/de 1509 Mycom II conductivity (ind.) BA 168C/07/de 150A Micropilot FMR 230 V BA 202F/00/de Micropilot FMR 231 BA 176F/00/de 150B Mycom II conductivity (cond.) BA 144C/07/ de 150C Mypro conductivity BA 198C/07/de 150D Mypro ph BA 198C/07/de 1510 Prowirl 77 BA 037D/06/de Liquisys in Vorbereitung 1514 FXN 164 I 343F/00/de RID 261 BA 098R/09/a3 052d ND800PA 7ND72en.pdf Explosion-hazardous areas Note! Electrical connection All components used in explosion-hazardous applications must have a FISCO approval. If this is not the case, the PROFIBUS-PA segment must be specially approved by the responsible authorities. All the Endress+Hauser and Metso devices listed above have been certified in accordance with the FISCO model. Note! In addition to the general installation guidelines, any special guidelines for installation in explosion-hazardous areas as well as the guidelines in Chapter 4.1 regarding the interconnection of devices in explosion hazardous areas must be observed. Connect up according to the instructions in the device operating manual. For devices with integrated polarity protection of the bus line, the correct polarity is automatically selected. If a device without polarity protection is incorrectly wired, then it will not be recognised by the PLC or operating program. Such an incorrect connection, however, has no damaging effect on the device or the segment. All Endress+Hauser and Metso devices have integrated polarity protection and can be commissioned independent of the actual polarity. 46 Metso Endress+Hauser

49 Addressing he device address can be set either locally via DIP switch, via local operating elements or by the appropriate software, e.g. Commuwin II. If future extensions to the network are planned, it makes sense to assign addresses for the devices that are not yet connected. hese can then be connected per plug and play at a later date. Address switch All Endress+Hauser devices except the temperature sensor MD 834 are fitted with an address switch = 10 on off SW HW Switches 1-7: Hardware address Switch 8: Hardware addressing (OFF) or Software addressing (ON) is used. he default setting is the software address 126. ND800PA address can be changed by using the local user interface. Hardware addressing has the advantage that the device can be installed in the segment immediately. Local user interface Hardware addressing 1) Set switch 8 to OFF. 2) Set an address with switches 1-7: the associated values are shown in the table. Switch No Value in position "off" Value in position "on" A software address can be set by calling the DPV1_DDE server in Commuwin II or by using a PROFIBUS-DP operating tool. Software addressing he device leaves the factory set for software addressing: Default address 126. his address can be used to check the function of the device and to connect it into an operating network. Afterwards, the address must be changed to allow other devices to be connected to the network. Metso Endress+Hauser 47

50 Commuwin II o set an address with Commuwin II proceed as follows: 1) Select software addressing at the device: set switch 8 of the address switch to ON 2) Start the DVP1 server with a double click on the DPV1 icon in the Commuwin II program group. 3) Select the item Set Address in the menu Configure. 4) If a type IM 157 Siemens DP/PA link is being used, enter its DP-address under PA Link Addr. 5) Enter the current address under Old Addr. (= 126 when commissioning).check the address entered by clicking on Check Old Address. If a device with the entered address is found, a message to this effect appears under Device ID. Otherwise the error message "unknown" appears. Set Device Address x Pa-Link Addr.: Old Addr.: Device Id: New Addr.: Device Id.: 34 MD 834 UNKNOWN Check Old Addr. Check New Addr. Set Address Help Cancel 6) Enter the new address in New Addr.Check that there is no address conflict by clicking on Check New Address. When the button Set Address becomes active, click on it to assign the new address to the device. Set Device Address x Pa-Link Addr.: Old Addr.: Device Id: New Addr.: Device Id.: 34 MD UNKNOWN Check Old Addr. Check New Addr. Set Address Help Cancel 7) When the procedure is completed correctly, the following message appears: "Address successfully changed!" 48 Metso Endress+Hauser

51 6 System Integration his chapter is concerned with the information that is required for the system integration of PROFIBUS-DP and PROFIBUS-PA devices. he chapter is structured as follows: Device database files Data format Notes on network design Bus parameters ested integrations 6.1 Device database files (GSD) A device database file contains a description of the properties of the PROFIBUS-PA device, e.g. the supported transmission rates and the type and format of the digital information output to the PLC. he bitmap files also belong to the.gsd files. hese allow the measuring point to be represented by an icon. he device database file and corresponding bitmaps are required by the network design tool of the PROFIBUS-DP network. Every device is allocated an identity code by the PROFIBUS User Organisation (PNO). his appears in the device data base file name (.gsd). For Endress+Hauser devices, the identity code is always 15xx, where xx is device dependent. he identity codes of the various devices are listed in able 4.5 in Chapter 4.3. Device name ID code.: GSD ype file Bitmaps Micropilot FMR 23x 150A (hex) EH 150A.gsd EH_150Ax.200 EH150A_d.bmp EH150A_n.bmp EH150A_s.bmp he full set of device data base files for Endress+Hauser and Metso devices can be obtained as follows: INERNE: Metso Automation Endress+Hauser Product Avenue Downloadstreet Field Communication Street PNO (GSD library) As diskette direct from Endress+Hauser: Order No he.gsd files must be loaded into a specific subdirectory in the PROFIBUS-DP network design software of your PLC. Working with GSD files GSD files and bitmaps that are located in the directory "ypdat5x", for example, are required for the planning software SEP7 used by the Siemens S7-300/400 PLC family. x.200 files and bitmaps that are located in the directory "Extended" are required for the planning software COM E200 for the Siemens S5. he GSD files located in the directory "standard" are for PLCs that support the "identifier byte" (0x94) but not the "identifier format". hese are for use e.g. with the Allen-Bradley PLC5. More details about the directories used for storing the GSD files can be found in Chapter 6.4, which describes the network design. Metso Endress+Hauser 49

52 6.2 Data format By using the data exchange service, a PLC can transmit its output data to a field device and read the input data from the response telegram. he output data is not evaluated by all devices, see the device operating instructions. Analogue values If the input/output data contains analogue measured or setpoint values, these are usually transmitted in 5 bytes to the PLC. byte 1 byte 2 byte 3 byte 4 byte 5 Measured value as IEEE 754 floating point number Status If a device delivers more than one measured value, the measured value telegram is increased accordingly, see Chapter 2.4. he number of measured values that a device transmits is set with the network design tool. able 4.7 in Chapter 4.6 as well as the device operating manuals summarise the measured values that can be transmitted by Endress+Hauser devices. he measured value is transmitted as a IEEE 754 floating point number, whereby Measured value = ( 1) Sign x 2 (E 127) x (1 + F) Fig. 6.1 IEEE-754 floating point number D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Sign Exponent (E) Fraction (F) Fraction (F) Example: 40 F hex = binary Value = ( 1) 0 x 2 ( ) x ( ) = 1 x2 2 x ( ) = 1 x 4 x = 7.5 Not all PLCs support the IEEE 754 format. For this reason a conversion module must often be used or written. Level limit signals If the field device outputs a level limit signal, e.g. FXA 164 with Liquiphant, the information is transmitted in 2 bytes as follows. An exact description of the transmission format is to be found in the operating instructions. bytes 1 bytes 2 Digital value (USGN8) Status 50 Metso Endress+Hauser

53 able 6.2 lists the status messages that can be transmitted by Endress+Hauser and Metso devices. he status codes correspond to the PROFIBUS profiles "PROFIBUS-PA Profile for Process Control Devices - General Requirements" V 2.0. Status he full table is supported by the flowmeters Promag, Promass and Prowirl. All other devices support only Codes 00Hex, 40Hex and 80Hex. Status- Code Significance Device status Implemented Flow Other 00 Hex Non-specific BAD x x 04 Hex Configuration error BAD x 08 Hex Not connected BAD x 0C Hex Device failure BAD x 10 Hex Sensor failure BAD x 14 Hex No communication (last usable value) BAD x 18 Hex No communication (no usable value) BAD x 1C Hex Out-of-order BAD x 20 Hex Configuration error "variable not" BAD x 40 Hex Non-specific (Simulation) UNCERAIN x x 44 Hex Last usable value UNCERAIN x 48 Hex Substitute set UNCERAIN x 4C Hex Initial value UNCERAIN x 50 Hex Sensor conversion not accurate UNCERAIN x 54 Hex Engineering unit range violation UNCERAIN x 58 Hex Subnormal UNCERAIN x 5C Hex Configuration error, value adapted UNCERAIN x 80 Hex OK GOOD x x 81 Hex LOW_LIM (alarm active) GOOD x 82 Hex HI_LIM (alarm active) GOOD x 84 Hex Active block alarm GOOD x 88 Hex Active advisory alarm GOOD x 8C Hex Active critical alarm GOOD x 90 Hex Unacknowledged block alarm GOOD x 94 Hex Unacknowledged advisory alarm GOOD x 98 Hex Unacknowledged critical alarm GOOD x 9C Hex good local operation possible GOOD x AC Hex Initiate fail-safe GOOD x able 6.1 Status messages Metso Endress+Hauser 51

54 6.3 Notes on network design In general, the design of a PROFIBUS-DP network proceeds as follows: 1. he network participants are stipulated in a PROFIBUS-DP network design program. he network is configured off-line with the planning software o this end, the GSD files are first loaded into the specified directory of the program. 2. he PLC application program must now be written. his is done using the manufacturer's software. he application program controls the input and output of data and determines where the data are to be stored. If necessary, an additional conversion module must be used for PLCs that do not support the IEEE 754 floating point format. Depending upon the way the data is stored in the PLC (LSB or MSB), a byte swapping module may be required. 3. After the network has been designed and configured, the result is loaded into the PLC as a binary file. 4. When the PLC configuration is complete, the system can be started up. he master opens a connection to each individual device. By using a Class 2 master, e.g. Commuwin II, the devices parameters can now be set. able 6.2 Examples of network design software System Master PROFIBUS configuration software Siemens Allen Bradley S5 Ö series S7 Ö series PLC-5 SLC-500 COM PROFIBUS HW Config HW Config SS PROFIBUS Configuration ool System- Programmingsoftware Step 5 Step 7 PCS 7 RS Logix-5 RS Logix-500 IEEE conv.- block FB 201 Schneider SX Premium Sycon Hilscher PL7 Pro yes Schneider Quantum Modicon Quantum Sycon Concept yes Klckner-Moller PS 416 CFG-DP S 40 yes ABB Freelance Field controller Digitool Digitool yes Bosch ZS 401 Win DP Win SPS yes bytes swap no no 52 Metso Endress+Hauser

55 6.4 ested system integrations able 6.3 lists those PROFIBUS-DP systems that have been successfully tested by Endress+Hauser. A detailed description of the network design as well as information on other systems is available on request. PLC Interface DP/PA-Coupler Siemens S DP P+F Siemens S DP Siemens Siemens S DP Siemens DP/PA link Siemens S DP P+F Siemens S DP Siemens Siemens S DP Siemens DP/PA link Siemens S5-135U IM 308C P+F Siemens S5-135U IM 308C Siemens Siemens S5-155U IM 308C P+F Siemens S5-155U IM 308C Siemens Siemens S5-155U IM 308C Siemens DP/PA link Allen Bradley PLC-5 SS-PFB-PLC5 P+F Allen Bradley PLC-5 SS-PFB-PLC5 Siemens DP/PA link Allen Bradley SLC 500 SS-PFB-SLC P+F Mitsubshi Melsec AnS A1S-J71PB92D P+F Schneider SX Quantum 140 CRP P+F Schneider Premium SX PBY 100 P+F HIMA H41 (MODBUS) PKV 20-DPM P+F Klckner-Mller PS 416 PS416-NE-440 P+F ABB Freelance 2000 Fieldcontroller P+F Softing OPC Server Profiboard/Proficard P+F Bosch CL 350 P BM DP12 P+F Bosch CL 350 P BM DP12 Siemens DP/PA link able 6.3 Summary of tested systems Metso Endress+Hauser 53

56 able 6.5 summarises the most important DP-parameters of various systems. PLC/interface DP/PA coupler No of slaves per DP interface DP telegram length able 6.4 Summary of tested systems Siemens S DP Siemens S DP Siemens S5-135U IM 308C Siemens S5-155U IM 308C Allen Bradley PLC-5 SS-PFB-PLC5 Allen Bradley SLC 500 SS-PFB-SLC Mitsubishi Melsec AnS A1S-J71PB92D Schneider SX Quantum CRP Schneider Premium + SX PBY 100 HIMA H41 (MODBUS) + PKV 20-DPM Klckner-Mller PS 416 +PS416-NE-440 ABB Freelance Fieldcontroller Bosch CL 350 P + BM DP12 1) dependent on the telegram length of the slaves P+F bytes Siemens bytes Siemens DP/PA link max. 64 links with max. 24 slaves each1) 122 bytes read 122 bytes write P+F bytes Siemens bytes Siemens DP/PA link max. 96 links with 122 bytes read max. 24 Slaves1) 122 bytes write P+F bytes read Siemens bytes write P+F bytes read Siemens bytes write Siemens DP/PA link max. 20 links with max. 24 slaves each1) 122 bytes read 122 bytes write P+F bytes read Siemens DP/PA link max. 125 links with 244 bytes write max. 48 slaves each1) P+F bytes read 244 bytes write P+F bytes read 244 bytes write P+F bytes read 244 bytes write P+F 125 max. 244 bytes P+F 125 max. 244 bytes P+F 30, 126 with repeaters 244 bytes read 244 bytes write P+F bytes read 244 bytes write P+F bytes read Siemens DP/PA link max. 125 links with 244 bytes write max. 48 slaves each1) 54 Metso Endress+Hauser

57 6.5 Bus parameters Endress+Hauser's PROFIBUS-DP devices support baudrates up to 12 Mbit/s. he baudrate is automatically adjusted to that used by the master. If Commuwin II is used as a Class 2 master to transmit acyclic values, then the bus parameters of the DPV1 DDE server must be matched to those of the segment coupler (or those of the network for PROFIBUS-DP applications). Baudrate, PROFIBUS-DP devices Operating program Commuwin II. Depending upon the segment coupler, the corresponding PROFIBUS-DP baudrate must be set in the network design software. Pepperl + Fuchs kbit/s Siemens kbit/s PA Link (Siemens) 9.6 kbit/s 12 Mbit/s he baudrate of Commuwin II must be set in the DPV1 DDE server. 1. Start the server DPV1 from the File Manager or Explorer by a double click on the DPV1 icon in the Commuwin II program group. 2. Open the item Parameter Settings in the Configure menu. he baudrate can now be adjusted. Communication Parameter Settings x Local Station Addr.: Baudrate [kbd]: 1 45,45 OK Cancel Help Bit imes Slot ime [SL]: 640 [6882 µs] Min St Delay [minsdr]: Max St Delay [max SDR]: Setup ime [SE]: [119 µs] [4302 µs] [1022 µs] arget Rotation ime [R]: [ µs] Default Higest Station Addr. [HSA]: Gap Update Factor: Max. Retry Limit:: After the baudrate has been entered, update the bus parameters by clicking on Default. 4. If necessary optimise the parameters as per able 6.3 or the manufacturer's specifications. Segment coupler Siemens P+F "old" P+F "new" 1) Slot time Max. station delay time Min. station delay time Setup time GAP update factor Max. retry limit arget rotation time 2) (R) R calculated by master bit times 1) he segment coupler has the label ) Value must be set in all masters. able 6.5 Bus parameters for Commuwin II Metso Endress+Hauser 55

58 7 Device Configuration here are two reasons for configuring a PROFIBUS-PA device: the adjustment of the operating parameters of the device to calibrate it for the application at hand. In this case the corresponding operating instructions should be used. the adjustment of the profile parameters of the device in order to e.g. scale or simulate the cyclic measured value output to the PLC. he operating parameters can be set using the local operating elements of the device, if it is so equipped. his is not described in this manual. hese parameters can also be adjusted by the acyclic services of the PROFIBUS-DP system, e.g. with the Commuwin II operating and display program. Profile parameters are accessible only through the cyclic services of the PROFIBUS-DP system. his chapter describes the operating concept of the PROFIBUS-PA devices. It is subdivided as follows: PROFIBUS-PA block model Device management Physical block ransducer block Function block Operating program Commuwin II. Oprating Simatic PDM Note! Note! he figures and tables in this chapter mostly refer to PROFIBUS-PA Profile 3.0 which will be released shortly. 56 Metso Endress+Hauser

59 7.1 PROFIBUS-PA block model he PROFIBUS-PA profile describes several parameters that can be used to realise a device. Mandatory parameters must always be present, Optional parameters are only present when required, e.g. for a particular transmitter type. Manufacturer-specific parameters are used to realise device functions that are not in the standard profile. A manufacturer's operating tool or a device description is required for their operation. In the case of PROFIBUS-PA devices that conform with the standard, these parameters are managed in block objects. Within the blocks, the individual parameters are managed using relative indices. Device management Physical block sensor signal ransducer block Function block output value of transmitter/ input value of PLC measured value Fig. 7.1 PROFIBUS-PA block model of a sensor Fig. 7.1 shows the block model of a simple sensor. It comprises four blocks: device management, physical block, transducer block and function block that are described in detail in the following sections. he sensor signal is converted to a measured value by the transducer block and transmitted to the function block. Here the measured value can be scaled or limits can be set before it is made available as the output value to the cyclic services of the PLC. Device management Physical block input value of actuator (set point)/ output value of PLC Function block ransducer block signal to valve output value Fig. 7.2 PROFIBUS-PA block model of an actuator For an actuator, the processing is in the reverse order, see Fig he PLC outputs a setpoint value that serves as the input value to the actuator. After any scaling, the setpoint value is transmitted to the transducer block as the output value of the function block. It processes the value and outputs a signal that drives the valve to the desired position. Metso Endress+Hauser 57

60 Block structure he parameters assigned to the individual blocks use the data structures and data formats that are specified in the PROFIBUS standard. he structures are designed such that the data are stored and transmitted in an ordered and interpretable manner. All parameters in the PROFIBUS-PA profile, whether mandatory or optional, are assigned an address (slot/index). he address structure must be maintained, even if optional parameters are not implemented in a device, his ensures that the relative indices in the profile are also to be found in the devices. Standard parameters With the exception of the device management, the standard parameters are to be found at the beginning of every block. hey are used to identify and manage the block. he user can access these parameters using the acyclic services, e.g. by means of the Commuwin II operating program. able 7.1 lists and briefly explains the standard parameters. Rel. Parameter Description R/W M/O Index able 7.1 Standard block parameters 1 BLOCKOB- JEC Contains the type of block, e.g. function block, as well as further classification information in the form of three storey a tree structure. 2 S_REV Event counter: Counts every access to a static block parameter. R M Static parameters are those device parameters that are not influenced by the process. 3 AG_DESC ext for unambiguous identification of the block: In the physical R, W M block, AG_DESC is used as the measuring point tag. 4 SRAEGY A code number that allows blocks to be grouped together. R, W M 5 ALER_KEY Identifies the part of the plant where the transmitter is located. R, W M Helps in the localisation of events. 6 MODE_BLK Describes the operating mode of the block. R, W M hree parameters are possible: actual mode permitted mode and normal mode MODE_BLK allows a functional check of the block. If the block is faulty, a default value can be output. 7 ALARM_SUM Contains the current status of the block alarms. At the moment R, W M only the following are signalled: the change of a static parameter (10 s) and the violation of the advisory and critical limits in the analog input block. 8 BACH Provided for batch processes as per IEC Part 1. Is only to R, W M be found in function blocks. R = Read, W = Write, M/O = Mandatory/Optional parameter R M 58 Metso Endress+Hauser

61 7.2 Device management he device management comprises the directory for the block and object structure of the device. It gives information about: which blocks are present in the device where the start addresses are located (slot/index) how many objects each block holds. By using this information, the application program of the master can find and transmit the mandatory and optional parameters of a profile block, see Fig Device Management (Slot 1) Slot x Slot y DIRECORY_OBJEC_HEADER DIR_ID REV_NUMBER NUM_DIR_OBJ NUM_DIR_EN FIRS_COMP_LIS_DIR_ENRY NUM_COMP_LIS_DIR_ENRY Index j FUNCION BLOCK 1 Index m FUNCION BLOCK 2 COMPOSIE_LIS_DIRECORY_ENRIES INDEX_PB NUM_PB INDEX B NUM_B INDEX_FB NUM_FB Index k PHYSICAL BLOCK 1 Index n RANSDUCER BLOCK 2 COMPOSIE_DIRECORY_ENRIES BLOCK_PR_1 BLOCK_PR_2 BLOCK_PR_3 BLOCK_PR_4... Index l RANSDUCER BLOCK 1 BLOCK_PR_# COMPOSIE_DIRECORY_ENRIES_CONINUOUS Fig. 7.3 Structure and function of the device management Device management block he device management is always located in slot 1 starting at index 0. It contains the following parameters: Abs. Parameter Description R/W M/O Index 8 SOFWARE_REVISION Software version implemented in device R M 0 DIRECORY_OBJEC_HEADER Header comprising (see Fig. 7.3 for parameter names) Directory code (=0) Directory version number Number of directory objects Number of directory entries Index of the first directory entry Number of block types R M 1 COMPOSIE_LIS_DIRECORY _ENRIES/ COMPOSIE_DIRECORY_ENRIES Pointer: Abs. index + offset, 1st physical block Number of physical blocks Abs. index + offset, 1st transducer blk. Number of transducer blocks Abs. index + offset, 1st function block Number of function blocks Pointer 1 to 1st block Pointer 2 to 2nd block... Pointer # to #th block M 2 COMPOSIE_DIRECORY_ENRIES_ CONINUOUS Continuation of COMPOSIE_ DIRECORY_ENRIES or start of the pointer entries W M able 7.2 Device management parameters Metso Endress+Hauser 59

62 7.3 Physical block he physical block contains the properties of the field device. hese are device parameters and functions that are not dependent upon the measurement method. his ensures that the function and transducer blocks are independent of the hardware. he physical block contains the following parameters: Rel. Parameter Description R/W M/O Index able 7.3 Physical block parameters 8 SOFWARE_REVISION Software version implemented in the device R M 9 HARDWARE_REVISION Hardware version implemented in the R M device 10 DEVICE_MAN_ID Manufacurerís identity code W M 11 DEVICE_ID Manuafacturerís name for the device R M 12 DEVICE_SER_NUM Serial number of the device R M 13 DIAGNOSIS Bit-coded uniform diagnostic messages R M 14 DIAGNOSIS_EXENSION Manufacturerís diagnostic messages R O 15 DIAGNOSE_MASK Bit mask that indicates the DIAGNOSIS bits R M supported. 16 DIAGNOSIS_EXENSION_MASK Bit mask that indicates the R O DIAGNOSIS_EXENSION bits supported 17 DEVICE_CERIFICAION ext describing the device certification R, W O 18 WRIE_LOCKING On/off switch for write protection R, W O 19 FACORY_RESE Command that resets the device e.g. to its W O factory settings 20 DESCRIPOR User text that describes the function of a R, W M device within an application 21 DEVICE_MESSAGE User text that describes the function of the R, W M device within its application or device unit 22 DEVICE_INSAL_DAE Installation date of the device R, W M 23 LOCAL_OP_ENA Enable/Disable of local operation R, W M 24 IDEN_NUMBER Specifies the configuration behaviour of the R, W M device on acknowledgement of the device identity code.dar 25 HW_WRIE_PROECION Shows the setting of a hardware jumper that R, W M activates ageneral write protection R = Read, W = Write, M/O = Mandatory/Optional parameter 60 Metso Endress+Hauser

63 he diagnostic messages are divided into standard (DIAGNOSE) and manufacturerspecific blocks (DIAGNOSE_EXENSION). A diagnostic message is supported when a "1" is to be found in the corresponding bit mask (_MASKE). he following statuses are to be found in the standard diagnostics. Diagnostic messages Octet Bit Parameter Description 1 0 DIA_HW_ELECR Fault in device electronics hardware 1 DIA_HW_MECH Mechanical device fault 2 DIA_EMP_MOOR Motor temperature too high 3 DIA_EMP_ELECR Electronics temperature too high 4 DIA_MEM_CHKSUM Memory error 5 DIA_MEASUREMEN Measured value error 6 DIA_NOR_INI Device not initialised 7 DIA_INI_ERR Intialisation error 2 0 DIA_ZERO_ERR Zero point error 1 DIA_SUPPLY Load supply error 2 DIA_CONF_INVAL Invalid configuration 3 DIA_WARMSAR Warm start in progress 4 DIA_COLDSAR Cold start in progress 5 DIA_MAINENANCE Maintenance necessary 6 DIA_CHARAC Invalid characteristic 7 IDEN_NUMBER_VIOLAION Violation of identity number reserved reserved 7 EXENSION_AVAILABLE Manufacturer's diagnostic messages available able 7.4 Standard diagnostic messages In the case of Endress+Hauser devices, a device error message is available when Bit 7 of Octet 4 is set (=1). hey are stored as 6 bytes in slot 1. For further information, see the corresponding field device. Metso Endress+Hauser 61

64 7.4 ransducer blocks ransducer blocks stand as separating elements between the sensor (or actuator) and the function block. hey process the signal from the sensor (or actuator) and output a value that is transmitted via a device-independent interface to the function block. he transducer blocks reflect the measurement (or actuator) principles. Moreover, blocks also exist for devices with a binary input or output signal- Fig shows the transducer blocks that are currently available. A description of the parameters can be taken from BA 124F (Commuwin II) or the appropriate device operating instructions. Measurement equipment A (Analysis) F (Flow) L (Level) P (Pressure, p) (emperature) Differential pressure Hydrostatic Resistance thermometer Electromagnetic Displacement hermocouple Ultrasonic Ultrasonics Pyrometer Vortex Microwave Positive displacement Capacitance Fig. 7.4 Summary of measuring methods implemented in transducer blocks (1999) Coriolis hermal Vibration Fig. 7.5 shows an example for a hydrostatic level transmitter. he functions indicated can be operated via the acyclic services. When Commuwin II is used Endress+Hauser devices can also be operated with the E+H matrix or graphic operation interface. Parameters can be read and written using the acyclic services PRESSURE (MAX_PRESSURE) (MIN_PRESSURE) (UNI) EMPY_CAL FULL_CAL DENSIY_FACOR LEVEL ZERO_OFFSE LIN_YPE LINEARISAION MAX_NUM_SUPPORED MAX_NUM_NEED INDEX INPU_VALUE OU_VALUE LINEARISAION CYL_DIAMEER CYL_VOLUME VOLUME SAUS l p v l v Fig. 7.5 Example for the transducer block of a hydrostatic level transmitter l 62 Metso Endress+Hauser

65 7.5 Function blocks he function blocks contain the basic automation functions. Since the application program demands that a cyclic value always behaves in the same manner, the blocks are designed to be as independent as possible from the actuator/sensor and the fieldbus. For transmitters there are currently three function blocks, which are described in more detail in the following pages. he analog input block is fed by the transducer block of a particular transmitter. he first function in the processing chain allows the measured value to be replaced by a simulated value when required. hen the input value is normalised to a value between 0 and 1. Normally, the lower and upper range values of the transducer block are used for scaling. No limits are set on the scaling values, and values beyond the end-values are correctly scaled. Analog input block he resulting value can now be linearised if required. Depending upon the setting, for example, a root function, a linearisation table or a preset linearisation might be activated. For Endress+Hauser devices with Profile 2.0, these functions are currently mapped on the transducer block. For devices with Profile 3.0 (available early in 2000) the linearisation will be mapped on the analog input block as described here. he normalised value is now scaled. If the "OU" value offered to the PLC is to be identical with the input value of the transducer block, then the lower and upper range values from the transducer block must again be used for scaling. Alternatively, other values can be used, e.g (20 215) in 15-bit resolution. An integration time and limits can now be assigned to the output value. Violations of the limits are signalled in the status byte. Finally the status of the output value is checked. he safety functions are activated when the status "BAD" or the mode "out of service" is detected. On fault condition a default value can be used as output value. he cyclic measured value made available to the DP master comprises the output value OU and the status. Parameters can be read and written using the acyclic services 1 0 PV OU HI_HI_ALM HI_ALM LO_ALM LO_LO_ALM ACUAL_MODE CHANNEL SIMULAION VALUE SAUS ON_OFF PV_SCALE PV_SCALE_UNI PV_SCALE_MIN PV_SCALE_MAX LIN_YPE OU_SCALE OU_SCALE_UNI OU_SCALE_MIN OU_SCALE_MAX PV_IME HI_HI_LIM HI_LIM LO_LIM LO_LO_LIM ALARM_HYS FSAFE_YPE FSAFE_VALUE MAN MODE_BLK NORMAL_MODE PERMIED_MODE MAN MODE/ SAUS 1 τ FAIL SAFE O/S AUO OU Alarms are indicated in the status byte Fig. 7.6 Schematic diagram of the analog input block Metso Endress+Hauser 63

66 otalisor block he totalisor block is used when a process variable must be summed over a period of time. his is the case for flowmeters, whereby for Endress+Hauser devices totalisors can be activated for both volume and mass measurements. he block is fed by the transducer block of a particular transmitter, which provides a measured value and status. he first function in the processing chain is a safety logic that checks the status of the input value. If the status is "BAD", the safety function is activated. hree options are now available: the bad value can be used for totalising, the last valid value can be used or the totaliser can be switched off. he safety function remains active until the status changes to "OK". he next function is the selection of counting mode. Four options are available: all values, positive values only, negative values only, no values at all. he value is now totalised by the counter. he counter can be set to work with equidistant timing or over time differences. It can also be reset to a preset value or zero. Limits may also be assigned to the totalisor. Violations of the limits are signalled in the status byte. Finally the status of the output value is checked. If the mode "out of service" is detected, the safe functions are activated. On fault condition a default value can be used as output value. he cyclic measured value made available to the DP master comprises the output value OAL and the status. Parameters can be read and written using the acyclic services HI_HI_ALM HI_ALM LO_ALM LO_LO_ALM ACUAL_MODE CHANNEL FAIL_O MODE_O SE_O PRESE_O UNI_O HI_HI_LIM HI_LIM LO_LIM LO_LO_LIM ALARM_HYS MAN_VALUE MODE_BLK NORMAL_MODE PERMIED_MODE MEMORY RUN HOLD FAIL SAFE BALANCED POS_ONLY NEG_ONLY HOLD Σ MAN O/S AUO MODE/ SAUS OAL Alarms are indicated in the status byte Fig. 7.7 Schematic diagram of the totaliser block 64 Metso Endress+Hauser

67 he discrete input block is used for limit switched, e.g. the Liquiphant (in connection with the FXA 164 NAMUR/PROFIBUS-PA interface). he analog input block is fed by a transducer block of a particular transmitter. Discrete input block he first function in the processing chain allows the measured value to be replaced by a simulated value when required. Afterwards the resulting signal can be inverted. Finally the status of the output value is checked. he safety functions are activated when the status "BAD" or the mode "out of service" is detected. On fault condition a default value can be used as output value. he cyclic measured value made available to the PROFIBUS-DP master comprises the output value OU_D and the status. Parameters can be read and written using the acyclic services ACUAL_MODE CHANNEL SIMULAION VALUE SAUS ON_OFF INVER FSAFE_YPE FSAFE_VAL_D MAN MODE_BLK NORMAL_MODE PERMIED_MODE MAN MODE/ SAUS INVER FAIL SAFE O/S OU_D AUO Fig. 7.8 Schematic diagram of the discrete input block Metso Endress+Hauser 65

68 7.6 Operating program Commuwin II. PROFIBUS-PA devices can be operated by the operating program Commuwin II (from software version 2.0 upwards) A full description of Commuwin II is to be found in operating instructions BA 124F. All the standard functions of Commuwin II are supported excepting envelope curves for ultrasonic and microwave devices. he device settings can be made using the operating matrix or graphic operating interface. Requirements Operation Commuwin II runs on an IBM-compatible PC or Laptop. he computer must be equipped with a PROFIBUS interface, i.e. PROFIBOARD for PCs and PROFICARD for laptops. During the system integration, the computer is registered as a Class 2 master. he PA-DPV1 server must be installed. he connection to Commuwin II is opened from the PA-DPV1 server. Generate a live list with "ags" Selection of the device operation Selection of profile operation FEB 24 PHY_20: LIC 123 LEVEL: LIC 123 AI: LIC CERABAR S PHY_30: PIC 205 Pressure PIC 205 AI: PIC E+H operation is selected by clicking on the device name, e.g. CERABAR S. Profile operation is selected by clicking on the appropriate tag, e.g. AI: PIC 205 = Analog input block Cerabar S. he settings are entered in the device menu. Device menu he device menu allows matrix or graphical operation to be selected. In the case of matrix operation, the device or profile parameters are displayed in a matrix. A parameter can be changed when the corresponding matrix field is selected. In the case of graphical operation, the operating sequence is shown in a series of pictures with parameters. For profile operation, the pictures Diagnosis, Scaling, Simulation and Block are of interest. he device parameters are set in accordance with the corresponding operating instructions. ables of profile functions are also to be found here. he parameter blocks are adapted to the transmitters: not all the functions shown in Fig 7.5 to Fig. 7.8 need be implemented. Devices from other vendors can also be operated via the profile parameters. In this case, standardised transducer, function or physical blocks appear. Off-line operation (E+H, Samson) Up-/download (E+H, Samson) Commuwin also allows the devices to be configured off-line. After all parameters have been entered, the file generated can be loaded into the connected device. his function allows the parameters of an already configured device to be loaded and stored in Commuwin II. If several devices (with the same software version) have to be configured in the same way, the parameters can now be downloaded into the devices. 66 Metso Endress+Hauser

69 Fig. 7.9 shows the graphic operation picture for the basic calibration of the Deltapilot S. Fig. 7.9 Basic calibration of the Deltapilot using Commuwin II Fig shows the graphical operation for the scaling of the Deltapilot S. By selecting the device profile "AI transmitter block" (acknowledge with ) the parameters PV_SCALE and OU_SCALE can be set. Please note that for DPV1 Version 2.0, the unit is not transmitted with the measured value. he setting of the PV unit also has no effect on the output value OU. he operating picture "Diagnosis" shows the current status of the device. "Simulation" allows a measured value to be simulated, "Block" displays the current setting of the mode block. Fig Scaling of the PA output of all devices using Commuwin II Metso Endress+Hauser 67

70 7.7 Operating Simatic PDM With Siemens Simatic PDM, it is possible to fully utilize the advanced diagnostic features of the Metso ND800PA positioner. For example the ND800PA key diagnostic trend, load factor, is presented in PDM as shown in the the figure 7.11 Fig 7.11 ND800PA Actuator load factor trend Fig 7.11 shows the load factor of the actuator as a percentage. In the case of a single acting actuator, the load factor shows the actuator load with respect to the present spring force, i.e., a load factor of 100% indicates that the actual load may exceed the spring force. For double acting actuators, the load factor shows the actuator load with respect to the user-given supply pressure level, i.e., a load factor of 100% indicates that the actual load may exceed maximum attainable pressure difference being equal to the supply pressure. he trend can be used for analysing the condition of the control valve. A high load factor indicates the presence of high friction or an undersized actuator if the given supply pressure is equal to actual supply pressure level. he load factor is not updated when the valve is appropriately fully open or closed. 68 Metso Endress+Hauser