MODBUS Protocol for MiCOM P30 Series

Transcription

1 MODBUS Protocol for MiCOM P30 Series Substation Protocols Technical Documentation This document does not replace the Technical Manual Version: MiCOM P30, MODBUS Index: B Release: 08 / 2011

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3 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] 3 NOTE The operating manual for this device gives instructions for its installation, commissioning and operation. However, the manual cannot cover all conceivable circumstances or include detailed information on all topics. In the event of questions or specific problems, do not take any action without proper authorization. Contact the appropriate technical sales office and request the necessary information. Any agreements, commitments, and legal relationships and any obligations on the part of the manufacturer, including settlement of warranties, result solely from the applicable purchase contract, which is not affected by the contents of this manual.

4 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] 4 CONTENT 1 General Transactions Serial Transmission Modes 5 2 Configuring the MODBUS Protocol 7 3 Function Codes Function Code 01 - Read Coil Status Function Code 02 - Read Input Status Function Code 03 - Read Holding Registers Function Code 04 - Read Input Register Function Code 05 - Force Single Coil Function Code 06 - Preset Single Register Function Code 07 Read Exception Status Function Code 08 Diagnostics Function Code 16 - Preset Multiple Registers 17 4 Error Handling, Exception Responses 18 5 Reading the Device Status and System Information Device Status System Information Register 19 6 Procedures Time Synchronization Event Handling Transmission of Disturbances and Long-Time Recorded Data Controlling Switching Devices 45 7 Appendix Appendix A - MODBUS Register Allocation, Setting Compatible Appendix B - MODBUS Register Allocation, Setting Private Appendix C MODBUS Registers for Signals and Measurements According to IEC

5 [Substation Protocols] MODBUS Protocol for MiCOM P30 Series 5 Transactions 1 General This document describes the specifics of the MODBUS implementation for MiCOM 30 Series devices. A general description of the MODBUS protocol can be found in the MODBUS specification. 1.1 Transactions MODBUS controllers communicate using a master-slave mechanism in which only one device (the master) can initiate transactions (called queries). The other devices (the slaves) respond by supplying the requested data to the master, or by taking the action requested in the query. The master can address individual slaves, or can initiate a broadcast message to all slaves. Slaves return a message (called a response) to queries that are addressed to them individually. No response is made to broadcast queries from the master. 1.2 Serial Transmission Modes MODBUS can communicate using either of two transmission modes: ASCII (American Standard Code for Information Interchange) RTU (Remote Terminal Unit). In the MiCOM 30 Series implementation only RTU mode is supported RTU Mode Coding system Bits per Byte 8-bit binary, hexadecimal 0-9, A-F Two hexadecimal chars in each 8-bit field of the message 1 start bit 8 data bits, least significant bit sent first 1 bit for even / odd parity; no bit for no parity 1 stop bit if parity is used; 2 bits if no parity

6 6 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Serial Transmission Modes RTU Framing START ADDRESS FUNCTION DATA CRC CHECK END T1-T2-T3-T4 8 BITS 8 BITS n x 8 BITS 16 BITS T1-T2-T3-T4 START ADDRESS FUNCTION DATA CRC CHECK END Silent interval of at least 3.5 character times Address field, slave device addresses 1-247, address 0 is used for broadcast Function code Data field, sets of RTU characters, can be nonexistent CRC value, 16 bit Silent interval of at least 3.5 character times

7 MODBUS Protocol for MiCOM P30 Series Serial Transmission Modes [Substation Protocols otocols] 7 2 Configuring the MODBUS Protocol It is important to note that activation and configuration of the MODBUS protocol for MiCOM 30 Series devices must be done via the local control panel or over the PC interface. Device data items do not have fixed indices but instead the user may configure the data items which are to be made available to the MODBUS master by selecting items from m out of n selection tables. MODBUS register allocation depends on the MODBUS variant selected. The register allocation for the two variants is as described in Appendix A and B. The protocol is available on the logical common interface 1 (COMM1) only. Configuration is done in the menu tree branch: P a r a m e t e r s \Config. parameters\comm1 The MODBUS protocol must be activated and the device address and parity must be correctly configured. The following device parameter is used to select which MODBUS variant is to be used. C O M M 1 : M O D B U S p r o t. v a r i a n t ( ) There are two MODBUS variants: Compatible Private The main difference between the two variants is the allocation of the MODBUS registers (see Appendix A and B). In the case of MODBUS variant Compatible, the following parameter is used to define whether automatic event acknowledgement is to be used (see Event Handling for MODBUS Variant Compatible ): C O M M 1 : Au t o m. e v e n t c o n f i r m. ( ) The following parameter is used to configure the behavior of the device when refreshing measurement values: C O M M 1 : D e l t a t ( M O D B U S ) ( ) This parameter defines the time in seconds after which measurement values are refreshed by the protection software in the device. The value of this parameter should be chosen carefully because changes in the value of a measurement within the configured time period are not registered.

8 8 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Serial Transmission Modes The information which MiCOM P30 Series devices make available to the MODBUS protocol can be divided into four groups: Binary information with read/write attribute Binary information with read only attribute Analog information with read/write attribute Analog information with read only attribute MODBUS register areas are defined contiguously so that more than one item of information may be accessed in a single query. Values in the device data model which are to be made available to the MODBUS protocol must be configured using the following parameters: C O M M 1 : R e g. a s g. s e l e c. c m d s ( ) This parameter is used to select from an m out of n selection table all the binary commands (read/write) which are to be made available to the MODBUS master. C O M M 1 : R e g. a s g. s e l e c. s i g. ( ) This parameter is used to select from an m out of n selection table all the binary signals (read only) which are to be made available to the MODBUS master. C O M M 1 : R e g. a s g. s e l. m. v a l. ( ) This parameter is used to select from an m out of n selection table all the analog measurements (read only) which are to be made available to the MODBUS master. C O M M 1 : R e g. a s g. s e l. p a r a m. ( ) This parameter is used to select from an m out of n selection table all the analog parameters (read/write) which are to be made available to the MODBUS master.

9 MODBUS Protocol for MiCOM P30 Series Function Code 01 - Read Coil Status [Substation Protocols otocols] 9 3 Function Codes The function code in a request telegram from a MODBUS master is used to specify whether the information in the slave device is to be read out or written to. It is important to note that data addressing differs according to which MODBUS variant has been selected (see 2 Configuring the MODBUS Protocol). 3.1 Function Code 01 - Read Coil Status Setting Compatible Setting Private Function code 01 is used to read binary information with read/write or read only attribute. A maximum of 1920 items can be read by a single query. Function code 01 is used to read binary information with read/write attribute. A maximum of 1920 items can be read by a single query. QUERY RESPONSE Slave Address Slave Address Function 01 Function 01 Starting Address Hi Register no. 1 st coil Byte Count (Data) Number of data bytes Starting Address Lo minus base register 1 Data 1 Coil status, No. of Points Hi Number of coils Data 2 starting with No. of Points Lo... data 1, bit 0 CRC Lo Data n 0 = OFF, 1 = ON CRC Hi CRC Lo CRC Hi 1 see Appendix A or B

10 10 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Function Code 02 - Read Input Status 3.2 Function Code 02 - Read Input Status Setting Compatible Setting Private Function code 02 is used to read binary information with read/write or read only attribute. A maximum of 1920 items can be read by a single query. Function code 02 is used to read binary information with read/write attribute. A maximum of 1920 items can be read by a single query. QUERY RESPONSE Slave Address Slave Address Function 02 Function 02 Starting Address Hi Register no. 1 st coil Byte Count (Data) Number of data bytes Starting Address Lo minus base register 2 Data 1 Coil status, No. of Points Hi Number of coils Data 2 starting with No. of Points Lo... data 1, bit 0 CRC Lo Data n 0 = OFF, 1 = ON CRC Hi CRC Lo CRC Hi 2 see Appendix A or B

11 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 11 Function Code 03 - Read Holding Registers 3.3 Function Code 03 - Read Holding Registers Setting Compatible Setting Private Function code 03 is used to read binary or analog information with read/write or read only attribute, or for reading events and recorded data. A maximum of 120 items of analog information can be read by a single query. When reading binary information, blocks of n*16 items must be read, where n may be a maximum of 120. Function code 03 is used to read analog information with read/write attribute. A maximum of 120 items can be read by a single query. QUERY RESPONSE Slave Address Slave Address Function 03 Function 03 Starting Address Hi Register no. 1 st coil Byte Count (Data) Number of data bytes Starting Address Lo minus base register 3 Data 1 Hi No. of Points Hi Number of information items Data 1 Lo Contents of registers No. of Points Lo... CRC Lo Data n Hi CRC Hi Data n Lo CRC Lo CRC Hi 3 see Appendix A or B

12 12 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Function Code 04 - Read Input Register 3.4 Function Code 04 - Read Input Register Setting Compatible Setting Private Function code 04 is used to read binary or analog information with read/write or read only attribute, or for reading events and recorded data. A maximum of 120 items of analog information can be accessed by a single query. When reading binary information, blocks of n*16 items must be read, where n may be a maximum of 120. Function code 04 is used to read analog information with read only attribute. A maximum of 120 items of information can be accessed by a single query. This function can also be used to read the event message registers and the recorded data message registers. QUERY RESPONSE Slave Address Slave Address Function 04 Function 04 Starting Address Hi Register no. 1 st coil minus base Byte Count (Data) Number of data bytes register 4 Starting Address Lo (word address) Data 1 Hi No. of Points Hi Number of information items Data 1 Lo Contents of registers No. of Points Lo... CRC Lo Data n Hi CRC Hi Data n Lo CRC Lo CRC Hi 4 see Appendix A or B

13 MODBUS Protocol for MiCOM P30 Series Function Code 05 - Force Single Coil [Substation Protocols otocols] Function Code 05 - Force Single Coil Setting Compatible Setting Private Function code 05 is used to write binary information with read/write attribute. Function code 05 is used to write binary information with read/write attribute. QUERY RESPONSE Slave Address Slave Address Function 05 Function 05 Coil Address Hi Register no. 1 st coil minus base Coil Address Hi Register no. 1 st coil register 5 minus base register 6 Coil Address Lo (bit address) Coil Address Lo (bit address) Force Data Hi 0000 (hex) = OFF Force Data Hi 0000 (hex) = OFF Force Data Lo FF00 (hex) = ON Force Data Lo FF00 (hex) = ON CRC Lo CRC Lo CRC Hi CRC Hi 5 see Appendix A or B 6 see Appendix A or B

14 14 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Function Code 06 - Preset Single Register 3.6 Function Code 06 - Preset Single Register Setting Compatible Setting Private Function code 06 is used to write analog information with read/write attribute and for acknowledging event and recorded data transmission. Function code 06 is used to write analog information with read/write attribute. This function can also be used to write the event command register, the event message registers and the recorded data message registers. QUERY RESPONSE Slave Address Slave Address Function 06 Function 06 Register Address Hi Register no. 1 st coil minus base Register Address Hi Register no. 1 st coil register 7 minus base register 8 Register Address Lo (word address) Register Address Lo (word address) Preset Data Hi Preset Data Hi Preset Data Lo Preset Data Lo CRC Lo CRC Lo CRC Hi CRC Hi 3.7 Function Code 07 Read Exception Status Setting Compatible Setting Private Function code 07 is used to read the exception status. Function code 07 is not supported. QUERY RESPONSE Slave Address Slave Address Function 07 Function 07 CRC Lo Coil Data Status CRC Hi CRC Lo CRC Hi 7 see Appendix A or B 8 see Appendix A or B

15 MODBUS Protocol for MiCOM P30 Series Function Code 08 Diagnostics [Substation Protocols otocols] Function Code 08 Diagnostics Setting Compatible Setting Private Function code 08 provides a series of diagnostic tests for checking communications between the master and slave or for checking various internal error conditions in the slave. Function code 08 provides a series of diagnostic tests for checking communications between the master and slave or for checking various internal error conditions in the slave. QUERY RESPONSE Slave Address Slave Address Function 08 Function 08 Subfunction Hi Subfunction Subfunction Hi Subfunction Subfunction Lo Subfunction Lo Data Hi Diagnostic data Data Hi Diagnostic data Data Lo Data Lo CRC Lo CRC Lo CRC Hi CRC Hi

16 16 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Function Code 08 Diagnostics Diagnostic Subfunction Codes Used Code (decimal) Name Function 00 Return Query Data 01 Restart Communications Option 04 Force Listen Only Mode 10 Clear Counters and Diagnostic Reg. Clears all counters. 11 Return Bus Message Count 12 Return Bus Comm. Error Count 13 Return Bus Exception Error Count 14 Return Slave Message Count 15 Return Slave No Respond Count 17 Return Slave BUSY Count 18 Return Bus Character Overrun Count The data passed in the query data field is to be returned (looped back) in the response. Initialize communication interface, clear all communication event counters, bring the interface out of Listen Only Mode. Forces the addressed slave to Listen Only Mode. All active communication controls are turned off. Messages or broadcasts are monitored, but no action will be taken and no response will be sent. Only the function Restart Communication option (function code 8, subfunction 1) will be processed. The response data field returns the number of messages detected by the slave. The response data field returns the number of CRC errors encountered by the slave. The response data field returns the number of MODBUS exception responses returned by the slave. The response data field returns the number of messages addressed to the slave or broadcast, that the slave has processed. The response data field returns the number of messages addressed to the slave for which it returned no response. The response data field returns the number of messages addressed to the slave for which it returned a Slave Device Busy. The response data field returns the number of messages addressed to the slave that it could not handle due to a character overrun condition.

17 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 17 Function Code 16 - Preset Multiple Registers 3.9 Function Code 16 - Preset Multiple Registers R Setting Compatible Setting Private Function code 16 is used for time synchronization. Function code 16 is used for time synchronization and for issuing commands for recorded data transfer. QUERY RESPONSE Slave Address Slave Address Function 16 Function 16 Starting Address Hi Register no. 1 st coil minus base Starting Address Hi Register no. 1 st coil register 9 minus base register 10 Starting Address Lo (word address) Starting Address Lo (word address) No. of Registers Hi Number of registers No. of Registers Hi Number of registers No. of Registers Lo No. of Registers Lo Byte Count CRC Lo Data 1 Hi Contents of registers CRC Hi Data 1 Lo... Data n Hi Data n Lo CRC Lo CRC Hi Contents of registers 9 see Appendix A or B 10 see Appendix A or B

18 18 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Function Code 16 - Preset Multiple Registers Master Query and Exception Response QUERY 4 Error Handling, Exception Responses One of four possible events can occur as a result of a query from the master: If the slave device receives the query without a communication error and can handle the query normally, it returns a normal response. If the slave does not receive the query due to a communication error, no response is returned. If the slave receives the query but detects a communication error (parity or CRC), no response is returned. If the slave receives the query without a communication error, but cannot handle it (for example if the request is to a non-existent coil or register), the slave returns an exception response informing the master of the nature of the error. In exception responses, the slave sets the most-significant bit of the function code to 1. RESPONSE Slave Address Slave Address Function 0x (binary) Function 1x (binary) CRC Lo CRC Hi Exception Codes Used Parameter or Exception Code structure CRC Lo depending on CRC Hi function code Code (decimal) Name Meaning 01 Illegal Function 02 Illegal Data Address 03 Illegal Data Value The function code received in the query is not an allowable action for the slave. The data address received in the query is not an allowable address for the slave. A value contained in the query is not an allowable value for the slave. 04 Slave Device Failure The slave has an internal communication error. 06 Slave Device Busy The slave is processing a long duration command.

19 MODBUS Protocol for MiCOM P30 Series Device Status [Substation Protocols otocols] 19 5 Reading the Device Status and System Information The device status and system information can be read only if variant Compatible is configured. 5.1 Device Status The MODBUS master uses function code 07 to read the device status. Bit Meaning x x x x x x x 0 Device is offline. x x x x x x x 1 Device is online. x x x x x x 1 x At least one entry in monitoring signal memory. x x x x x 1 x x Event(s) present. x x x x 0 x x x Time synchronization: device is not synchronized. x x x x 1 x x x Time synchronization: device is synchronized. x x x 1 x x x x Recorded data present. 5.2 System Informa mation Register The MODBUS master uses function code 03 or 04 to read the system information from register (decimal). Bit Meaning x x x 0 x x x x x x x x x x x x Without automatic event acknowledgement. x x x 1 x x x x x x x x x x x x With automatic event acknowledgement. x x 1 x x x x x x x x x x x x x Event ring buffer overflow. x 1 x x x x x x x x x x x x x x Recording memory overflow.

20 20 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Time Synchronization 6 Procedures 6.1 Time Synchronization Setting Compatible Setting Private The time is kept in four registers in IEC CP56Time2a format in reverse order. The time is kept in four registers in IEC CP56Time2a format in reverse order. Register (decimal) Register contents Compatible Private Year Month DOW DOM SU 0 0 Hours IV 0 Minutes Milliseconds Milliseconds Note: DOW - Day of week (1: Monday) DOM SU - Day of month - Summer time (0: standard time, 1: daylight saving time) IV - Invalid (0: valid, 1: invalid) Time synchronization is done according to IEC The MODBUS Master sends the time to the slave(s) using function code 16 ( Preset Multiple Registers ). A slave adjusts the time taken from the telegram (taking into account the elapsed communication and internal processing time) and sets its internal clock. The newly set time is written to the time synchronization registers so that the master can check that time synchronization was successful. Note! All fields must be provided in a time synchronization telegram.

21 MODBUS Protocol for MiCOM P30 Series Event Handling [Substation Protocols otocols] Event Handling All MiCOM 30 Series devices have a ring buffer for storing the most recent 100 state changes (referred to as events). Event transmission is handled differently depending on the configured MODBUS variant Event Handling for MODBUS Variant Compatible If more events occur than can fit in the ring buffer, the oldest event is overwritten by the new event. In addition, bit 13 of the system information register (see 5.2 System Information Register) is set, and an additional event buffer overflow start is generated with register number and contents of the system information register. When an event has been read and acknowledged, the event is deleted from the ring buffer, bit 13 of the system information register is reset and an additional event buffer overflow end is generated with register number and contents of the system information register. For this MODBUS variant there are two possible modes for event transmission: Event transmission without automatic event acknowledgement Event transmission with automatic event acknowledgement The mode can be selected under C O M M 1 : Au t o m. e v e n t c o n f i r m. ( ).

22 22 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Event Handling Event Transmission without Automatic Acknowledgement In this mode the MODBUS master sends a telegram with function code 03 or 04 to read register (decimal). The MODBUS slave device returns the oldest event. If the master receives the event successfully, it sends a telegram with function code 06 to write to register (decimal), acknowledging receipt of the event. The slave responds by echoing the telegram, deletes the event from the ring buffer, and may reset bit 2 of the device status register (see 5.1 Device Status) and bit 13 of the system information register (see 5.2 System Information Register) where appropriate. If the master detects an error during reception of the event, the master may read register (decimal) again to retrieve the same event. If the slave device has no events to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses). Figure 1 shows the basic logic for event transmission without automatic acknowledgement: MODBUS Master MODBUS Slave Read Device Status Send Device Status, bit 2 = 1 optional Read Event Send Event Send Event Acknowledgement Confirm Event Acknowledgement 1 Logic for Event Transmission without Automatic Acknowledgement

23 MODBUS Protocol for MiCOM P30 Series Event Handling [Substation Protocols otocols] 23 Reading and Sending the Device Status (Event Present) QUERY The following tables show the contents of the telegrams for event transmission without automatic acknowledgement: RESPONSE Slave Address Slave Address Function Code 07 Function Code 07 CRC Lo Coil data Bit 2 = 1 CRC Hi CRC Lo Reading and Sending an Event QUERY CRC Hi RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi 36 (hex) Byte Count (Data) 12 (hex) Starting Address Lo 00 (hex) Data 1 Hi Event No. of Points Hi 00 (hex) Data 1 Lo No. of Points Lo 09 (hex)... CRC Lo Data 9 Hi CRC Hi Data 9 Lo Acknowledging an Event QUERY CRC Lo CRC Hi RESPONSE Slave Address Slave Address Function Code 06 Function Code 06 Register Address Hi 04 (hex) Register Address Hi 04 (hex) Register Address Lo 00 (hex) Register Address Lo 00 (hex) Preset Data Hi 20 (hex) Preset Data Hi 20 (hex) Preset Data Lo 00 (hex) Preset Data Lo 00 (hex) CRC Lo CRC Lo CRC Hi CRC Hi

24 24 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Event Handling Event Structure Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Data 8 Data 9 Reserved Value Register Reserved Time stamp (inverted CP56Time2a) Reserved

25 MODBUS Protocol for MiCOM P30 Series Event Handling [Substation Protocols otocols] 25 Event Transmission with Automatic Acknowledgement In this mode the MODBUS master sends a telegram with function code 03 or 04 to read register (decimal). The MODBUS slave device returns the oldest event. The slave deletes the event from the ring buffer and may reset bit 2 of the device status register (see 5.1 Device Status) and bit 13 of the system information register (see 5.2 System Information Register) where appropriate. If the master detects an error during reception of the event, the master may read register (decimal) to retrieve the same event. If the slave device has no events to send, or if the master reads register (decimal) without first reading register (decimal), the slave will respond with an exception response code 04 (see 4 Error Handling, Exception Responses). Figure 2 shows the basic logic for event transmission with automatic acknowledgement: MODBUS Master MODBUS Slave Read Device Status Send Device Status, bit 2 = 1 optional Read Event Send Event 2 Logic for Event Transmission with Automatic Acknowledgement

26 26 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Event Handling Reading and Sending the Device Status (Event Present) QUERY The following tables show the contents of the telegrams for event transmission with automatic acknowledgement: RESPONSE Slave Address Slave Address Function Code 07 Function Code 07 CRC Lo Coil data Bit 2 = 1 CRC Hi CRC Lo Reading and Sending an Event QUERY CRC Hi RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi 36 (hex) Byte Count (Data) 12 (hex) Starting Address Lo 00 (hex) / 01 (hex) Data 1 Hi Event No. of Points Hi 00 (hex) Data 1 Lo No. of Points Lo 09 (hex)... CRC Lo Data 9 Hi CRC Hi Data 9 Lo Event Structure CRC Lo CRC Hi Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Data 8 Data 9 Reserved Value Register Reserved Time stamp (inverted CP56Time2a) Reserved

27 MODBUS Protocol for MiCOM P30 Series Event Handling [Substation Protocols otocols] Event Handling for MODBUS Variant Private MODBUS registers are updated when state changes occur. In addition, event telegrams are generated for all registers in the 0 range, for external device registers, and for disturbance measurements. Each event is stored in a ring buffer along with a time stamp. If the ring buffer is full, the oldest event is overwritten by the new event and the ring buffer overflow is flagged. Event handling is done using the event command register and the event message registers. Event Message Registers Register content Register (decimal) Meaning Number of events Number of events in the ring buffer Function code Hi: default = 0 ring buffer overflow = FF (hex) Lo: function code depending on register range Event register number Register or bit address of the event Event data Binary: Analog: Year Event time stamp Month / Day Hour / Minute Milliseconds bit 0 = Information bits 1 to 15 = 0 register contents Event Command Register Register content Register (decimal) Event command Meaning Event command register 0000 (hex) - Read next event 0001 (hex) - Reread last event FFFF (hex)- Delete ring buffer

28 28 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Event Handling The number of events register (decimal) contains the number of event telegrams currently stored in the ring buffer. The master can cyclically poll this register to check for events. Registers (decimal) to (decimal) contain the data from the last event which was read. The event command is initialized to 0. When registers (decimal) to (decimal) have been read and there is at least one event present in the ring buffer, the oldest event is copied to these registers and the number of events is decremented. The master can reread the previous event by setting the event command register to 0001 (hex). This is useful when a transmission error has occurred. The master can also reread registers outside the range (decimal) to (decimal).

29 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 29 Transmission of Disturbances and Long-Time Recorded Data 6.3 Transmission of Disturbances and Long-Time Recorded Data Transmission of recorded data is handled differently depending on the configured MODBUS variant Transmission of Recorded Data for MODBUS Variant Compatible All MiCOM 30 Series devices have memory for storing analog samples for a maximum of eight recordings. There are two possible modes for transmission of recorded data: Recorded data upload by column File upload Recorded Data Upload by Column Figure 3 shows the basic logic for mode upload by column :

30 30 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data MODBUS Master MODBUS Slave Read Device Status Send Device Status,bit 4 = 1 optional Read Recording Information Send Recording Information Read Channel 1 Data Send Channel 1 Data Read First Block of Samples for Channel 1 Send First Block of Samples for Channel Read Last Block of Samples for Channel 1 Send Last Block of Samples for Channel Read Channel 8 Data Send Channel 8 Data Read Last Block of Samples for Channel 8 Send Last Block of Samples for Channel 8 Read Recording Index Send Recording Index Send Acknowledgement of Reading of Recording Confirm Acknowledgement of Reading of Recording 3 Logic for Transmission of Recorded Data in Mode Upload by Column

31 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 31 Transmission of Disturbances and Long-Time Recorded Data The following tables show the contents of the telegrams for mode upload by column : Reading and Sending the Device Status (Recorded Data Present) QUERY RESPONSE Slave Address Slave Address Function Code 07 Function Code 07 CRC Lo Coil data Bit 4 = 1 CRC Hi CRC Lo CRC Hi Reading and Sending of Recorded Data QUERY RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi 60 (hex) Byte Count (Data) 0C (hex) Starting Address Lo 00 (hex) Data 1 Hi No. of Points Hi 00 (hex) Data 1 Lo No. of Points Lo 06 (hex)... CRC Lo Data 6 Hi CRC Hi Data 6 Lo CRC Lo CRC Hi Structure of Recorded Data Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Channel information register for channel 1: (decimal) Recording read acknowledgement register: (decimal) Number of channels Maximum number of samples per block: 100 (decimal) Register of first block: (decimal) Register of last block If the slave device has no events to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses).

32 32 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data Reading and Sending of the Data for a Channel QUERY RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi Channel information Byte Count (Data) 1C (hex) Starting Address Lo register Data 1 Hi Channel data No. of Points Hi 00 (hex) Data 1 Lo No. of Points Lo 0E (hex)... CRC Lo Data 14 Hi CRC Hi Data 14 Lo CRC Lo CRC Hi Channel Data Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Data 8 Data 9 Data 10 Data 11 Data 12 Data 13 Data 14 Number of samples Number of samples in the pre-fault time Number of samples in the post-fault time Transformation ratio, primary voltage Transformation ratio, secondary voltage Transformation ratio, primary current Transformation ratio, secondary current Internal voltage scaling factor Internal current scaling factor Register of first block of samples Register of last block of samples Number of samples in last block Sampling frequency Channel type

33 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 33 Transmission of Disturbances and Long-Time Recorded Data Contents of the Channel Type Field (Channel Information Data Item 14) Value Meaning 1 IA 2 IB 3 IC 4 IN 5 VA-G 6 VB-G 7 VC-G 8 VN-G Reading and Sending a Block of Samples for a Channel QUERY If the slave device has no recorded data to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses). RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi Block register Byte Count (Data) Starting Address Lo No. of Points Hi No. of Points Lo Number of samples in block Data 1 Hi Value of sample 1 Data 1 Lo CRC Lo Data n Hi Value of sample n CRC Hi Data n Lo... CRC Lo CRC Hi When a block of samples for a channel is read, all samples must be read. This means that the number of samples is always 100. For the last block, the number of samples is the value in the field number of samples in last block (channel information data item 12). A primary measurement value is calculated by multiplying the value of the sample by the internal scaling factor of the voltage or current. If the slave device has no recorded data to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses).

34 34 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data Reading and Sending the Recording Index QUERY RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi 61 (hex) Byte Count (Data) 12 (hex) Starting Address Lo 80 (hex) Data 1 Hi Recording index No. of Points Hi 00 (hex) Data 1 Lo No. of Points Lo 09 (hex)... CRC Lo Data 9 Hi CRC Hi Data 9 Lo CRC Lo CRC Hi Structure of Recording Index Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Data 8 Data 9 Recording number Time stamp (inverted CP56Time2a) Cause Sampling frequency Version number of the conversion tool Revision number of the conversion tool If the slave device has no recorded data to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses).

35 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 35 Transmission of Disturbances and Long-Time Recorded Data Sending and Confirming Acknowledgement of Reading of Recording QUERY RESPONSE Slave Address Slave Address Function Code 06 Function Code 06 Register Address Hi 04 (hex) Register Address Hi 04 (hex) Register Address Lo 00 (hex) Register Address Lo 00 (hex) Preset Data Hi 10 (hex) Preset Data Hi 10 (hex) Preset Data Lo 00 (hex) Preset Data Lo 00 (hex) CRC Lo CRC Lo CRC Hi CRC Hi If no recorded data has been read, the slave will respond with an exception response code 04 (see 4 Error Handling, Exception Responses).

36 36 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data File Upload Figure 4 shows the basic logic for mode file upload : MODBUS Master MODBUS Slave Read Device Status Send Device Status, bit 4 = 1 optional Read Header Send Header Read Channel Information Send Channel Information Read First Block of Samples Send First Block of Samples Read Last Block of Samples Send Last Block of Samples Send Acknowledgement of Reading of Recording Confirm Acknowledgement of Reading of Recording 4 Logic for Transmission of Recorded Data in Mode File Upload

37 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 37 Transmission of Disturbances and Long-Time Recorded Data The following tables show the contents of the telegrams for transmission of recorded data in mode file upload : Reading and Sending the Device Status (Recorded Data Present) QUERY RESPONSE Slave Address Slave Address Function Code 07 Function Code 07 CRC Lo Coil data Bit 4 = 1 CRC Hi CRC Lo CRC Hi Reading and Sending of the Header QUERY RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi 61 (hex) Byte Count (Data) 30 (hex) Starting Address Lo 90 (hex) Data 1 Hi Header No. of Points Hi 00 (hex) Data 1 Lo No. of Points Lo 18 (hex)... CRC Lo Data 24 Hi CRC Hi Data 24 Lo CRC Lo CRC Hi

38 38 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data Structure of the Header Data 1 Data transmission type: Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Data 8 Data 9 Data 10 Data 11 Data 12 Data 13 Data 14 Data 15 Data 16 Data 17 Data 18 Data 19 Data 20 Data 21 Data 22 Data 23 Data 24 Number of channel information data items: 36 (decimal) Number of samples per channel Manufacturer Product designation Version number of the transmission mechanism Device serial number Type of transmission: 0003 (hex) = recorded data transmission Time stamp (inverted CP56Time2a) Reserved If the slave device has no recorded data to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses).

39 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 39 Transmission of Disturbances and Long-Time Recorded Data Reading and Sending of the Channel Information QUERY RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi 61 (hex) Byte Count (Data) 48 (hex) Starting Address Lo B0 (hex) Data 1 Hi Channel information No. of Points Hi 00 (hex) Data 1 Lo No. of Points Lo 24 (hex)... CRC Lo Data 36 Hi CRC Hi Data 36 Lo CRC Lo CRC Hi

40 40 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data Structure of the Channel Information Data 1 Number of channels Data 2 Type of channel 1 Data 3 Transformation ratio, primary Data 4 Transformation ratio, secondary Data 5 Internal scaling factor Data 6 Type of channel 2 Data 7 Transformation ratio, primary Data 8 Transformation ratio, secondary Data 9 Internal scaling factor Data 10 Type of channel 3 Data 11 Transformation ratio, primary Data 12 Transformation ratio, secondary Data 13 Internal scaling factor Data 14 Type of channel 4 Data 15 Transformation ratio, primary Data 16 Transformation ratio, secondary Data 17 Internal scaling factor Data 18 Type of channel 5 Data 19 Transformation ratio, primary Data 20 Transformation ratio, secondary Data 21 Internal scaling factor Data 22 Type of channel 6 Data 23 Transformation ratio, primary Data 24 Transformation ratio, secondary Data 25 Internal scaling factor Data 26 Type of channel 7 Data 27 Transformation ratio, primary Data 28 Transformation ratio, secondary Data 29 Internal scaling factor Data 30 Type of channel 8 Data 31 Transformation ratio, primary Data 32 Transformation ratio, secondary Data 33 Internal scaling factor Data 34 Sampling frequency Data 35 Recording number Data 36 Number of samples per channel

41 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 41 Transmission of Disturbances and Long-Time Recorded Data Contents of the Channel Type Field (Channel Information Data Items 2, 6, 10, 14, 18, 22, 26, 30) Value Meaning 1 IA 2 IB 3 IC 4 IN 5 VA-G 6 VB-G 7 VC-G 8 VN-G Reading and Sending a Block of Samples QUERY If the slave device has no recorded data to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses). RESPONSE Slave Address Slave Address Function Code 03 or 04 Function Code 03 or 04 Starting Address Hi Block register Byte Count (Data) Starting Address Lo No. of Points Hi No. of Points Lo Number of samples in block Data 1 Hi Data 1 Lo Data 2 Hi CRC Lo Data 2 Lo CRC Hi Data n Hi Data n Lo CRC Lo CRC Hi Value of sample 1 Value of sample 2 Value of sample n When a block of samples for a channel is read, all samples must be read. This means that the number of samples is always 100, with the exception of the last block which may have less samples. If the slave device has no recorded data to send, it will respond with an exception response code 04 (see 4 Error Handling, Exception Responses).

42 42 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data Sending and Confirming Acknowledgement of Reading of Recording QUERY RESPONSE Slave Address Slave Address Function Code 06 Function Code 06 Register Address Hi 04 (hex) Register Address Hi 04 (hex) Register Address Lo 00 (hex) Register Address Lo 00 (hex) Preset Data Hi 10 (hex) Preset Data Hi 10 (hex) Preset Data Lo 00 (hex) Preset Data Lo 00 (hex) CRC Lo CRC Lo CRC Hi CRC Hi If no recorded data has been read, the slave will respond with an exception response code 04 (see 4 Error Handling, Exception Responses).

43 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 43 Transmission of Disturbances and Long-Time Recorded Data Transmission of Recorded Data for MODBUS Variant Private All MiCOM 30 Series devices have memory for storing a maximum of eight recordings with the following data which can be read if MODBUS variant Private is configured: Binary data Disturbance measurements Analog samples Recorded Data Message Registers Recorded Data Command Register Transmission of recorded data is done by reading the the disturbance or long-time recording information from the recorded data registers and by writing the command or acknowledgement telegrams to the recorded data command registers. The following registers are used for the transmission of recorded data: Register content Register (decimal) Number of telegrams Type ID Variable structure ID Cause of transmission Device address Function type Information number Data structure according to ASDU 23, 26, 27, 28, 29, 30, according to IEC Register content Register (decimal) Command Meaning Transfer command register: 0000 (hex) - Read next telegram 0001 (hex) - Reread previous telegram FFFF (hex)- Initialize transfer

44 44 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Transmission of Disturbances and Long-Time Recorded Data Recorded Data Order Registers Register content Register (decimal) Type ID Variable structure ID Cause of transmission Device address Function type Information number Type of order Type of recorded data Recording number Lo Recording number Hi Channel number The telegrams for information transfer are kept in a ring buffer. The number of telegrams can be read from register (decimal). After initialization, the telegram list of recordings is present in the ring buffer. The procedures for reading from the recorded data message registers use the same mechanisms as the event handling logic, depending on the contents of the recorded data command register. The next telegram can be read by writing a read command to registers (decimal) to (decimal). The MODBUS master writes ASDU 24 ( recorded data transfer order ) and ASDU 25 ( recorded data transfer acknowledgement ) commands to the recorded data order registers in IEC format.

45 MODBUS Protocol for MiCOM P30 Series Controlling Switching Devices [Substation Protocols otocols] Controlling Switching Devices MiCOM 30 Series devices offer the possibility of controlling switching devices over their serial interfaces. A register (called an external device register) is defined for each switching device. The following tables show how these registers are used. It is important to note that the structure depends on whether variant Compatible or Private is selected. Structure of the External Device Register for MODBUS Variant Compatible Bit Meaning x x x x x x x x x x x x x Position: open x x x x x x x x x x x x x Position: closed x x x x x x x x x x x x x Position: off-end x x x x x x x x x x x x x Position: faulty x x x x x x x x x x x x 0 x x x Local control x x x x x x x x x x x x 1 x x x Remote control x x x x x x x x x x x 0 x x x x Unlocked x x x x x x x x x x x 1 x x x x Locked x x x x x x x x x x 0 x x x x x Reserved x x x x x x x x x 0 x x x x x x Reserved x x x x x x x x 1 x x x x x x x Error: CB running monitor timeout x x x x x x x 1 x x x x x x x x Error: target position = actual position x x x x x x 0 x x x x x x x x x Reserved x x x x x 1 x x x x x x x x x x Error: interlocking conditions not met x x x x 1 x x x x x x x x x x x Enable command execution x x x x x x x x x x x x Switch command: open x x x x x x x x x x x x Switch command: close Note: - Bits 0 to 11: binary state information is read only for the master and masked for write operation. - Bits 12 to 15: binary state is written by the master. After command execution, the binary state is cleared.

46 46 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Controlling Switching Devices Structure of the External Device Register for MODBUS Variant Private Bit Meaning x x x x x x x x x x x x x x 0 0 Position: off-end x x x x x x x x x x x x x x 0 1 Position: open x x x x x x x x x x x x x x 1 0 Position: closed x x x x x x x x x x x x x External device not present x x x x x x x x x x x x x Single signal x x x x x x x x x x x x x Double signal x x x x x x x x x x x x x Single command x x x x x x x x x x x x x Single signal with command x x x x x x x x x x x x x Double signal with command x x x x x x x x x 0 1 x x x x x Signal: local open command x x x x x x x x x 1 0 x x x x x Signal: local close command x x x x x x x 0 1 x x x x x x x Command execution enabled x x x x x x x 1 0 x x x x x x x Command execution disabled x x x x x 0 1 x x x x x x x x x Command execution successful x x x x x 1 0 x x x x x x x x x Command execution aborted x x x x 1 x x x x x x x x x x x Error: interlocking conditions not met x x x x x x x x x x x x Switch command: open x x x x x x x x x x x x Switch command: close Note: - Bits 0 to 11: binary state information is read only for the master and masked for write operation. - Bits 12 to 15: binary state is written by the master. After command execution, the binary state is cleared.

47 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 47 Appendix A - MODBUS Register Allocation, Setting Compatible Base register (decimal) 7 Appendix 7.1 Appendix A - MODBUS Register Allocation, Setting S Compatible Compatible The following table shows MODBUS register allocation for the Compatible variant: Register (decimal) Information in registers Data Type Attribute not used / Used by function codes (decimal) system information, read only acknowledgement of events / recorded data write only not used / time synchronization not used not used binary read only / single-pole signals in function group SIG_1 in ascending order according to m out of n selection COMM1: Reg.asg. selec. sig. ( ) according to IEC (see Appendix C) according to IEC (see Appendix C) according to m out of n selection COMM1: Reg.asg. selec. cmds ( ) single-pole commands in function group CMD_1 in ascending order binary read only binary read only binary read only binary binary read/write read/write binary read/write not used binary write only not used / , , event transmission read only not used not used according to IEC (see Appendix C) according to m out of n selection COMM1: Reg.asg. sel. m.val. ( ) analog read only analog read only

48 48 MODBUS Protocol for MiCOM P30 Series [Substation Protocols] Appendix A - MODBUS Register Allocation, Setting Compatible Base register (decimal) Register (decimal) Information in registers Data Type Attribute according to m out of n selection COMM1: Reg.asg. sel. param. ( ) external device registers (switching device control) analog analog read/write read/write not used analog write only recorded data transmission Used by function codes (decimal) , , 06

49 MODBUS Protocol for MiCOM P30 Series [Substation Protocols otocols] 49 Appendix B - MODBUS Register Allocation, Setting Private Base register (decimal) 7.2 Appendix B - MODBUS Register Allocation, Setting Private Private The following table shows MODBUS register allocation for the Private variant: Register (decimal) not used not used not used not used not used Information in registers Data Type Attribute according to IEC (see Appendix C) according to m out of n selection COMM1: Reg.asg. selec. cmds ( ) single-pole commands in function group CMD_1 in ascending order according to IEC (see Appendix C) according to m out of n selection COMM1: Reg.asg. selec. sig. ( ) status signals from single-pole commands in function group CMD_1 in ascending order single-pole signals in function group SIG_1 in ascending order according to IEC (see Appendix C) Used by function codes (decimal) binary read/write 01, 05 binary read/write 01, 05 binary write only 05 binary read only 02 binary read only 02 binary read only 02 binary read only 02 analog read only event message registers analog read only not used not used recorded data message registers according to m out of n selection COMM1: Reg.asg. sel. m.val. ( ) analog read only 04 analog read only 04