Cutler-Hammer Ethernet Products Modicon Quantum PLC Connectivity Application Note

Transcription

1 Cutler-Hammer Ethernet Products Modicon Quantum PLC Connectivity Application Note Originator: Les Nyulak Region: British Columbia Overview of Quantum Modbus/TCP Connectivity to Cutler-Hammer Products The Modicon NOE EtherNet card acts as a master to the D77D-EMA adapter in the application. All data exchange occurs via 4xxxxx holding registers. At the time of writing, Cutler-Hammer s CHStudio network configuration software did not support the EMA. The EMA adapter passes ModBus messages embedded in EtherNet packets (Modbus/TCP) through to the QC Scanner Ports on the EMA (Channel A or B). As a side note, these ports can also be configured as Modbus ports The scope of this application note extends only to QCPort data exchange. It is assumed that the user has familiarity with both Ethernet network management tools and Concept Programming software. List of Materials All items listed below where the exact models used to perform the test. Any variation of items could produce different results. A new application note should be generated for each variation. Item Manufacturer Catalog Number / Version Modbus register tool Win-tech Modscan v4.b00-09 Network Hub SMC Barricade G switching router EtherNet Card 3COM 3C920 I Fast Ethernet Controller Motor Control Adaptor Eaton Electrical D77D-EMA Breaker Cover Control Eaton Electrical N/a Motor Starter Eaton Electrical N101BSAX3N BootP Server Rockwell Software BootP Standalone v PLC CPU Modicon (Groupe Schneider) 140 CPU Modbus Programming Cable Modicon (Groupe Schneider) 990 NAA Quantum Programming s/w Modicon (Groupe Schneider) Concept v2.5 Modbus/TCP Scanner Card Modicon (Groupe Schneider) 140 NOE Configuration of D77D-EMA The configuration of the EMA and QCPort subnetwork components is well documented by related Eaton literature (see Appendix for literature references). This section will serve as a quick start overview using only the default setup for components. The out-of-box defaults for the cover control give you 6 bytes of input (feedback) data and 1 byte of output (control) data. The EMA itself has two bytes of input data and 2 bytes of output data for feedback and control of scanning on QCPort Channels A & B. One Cover Control was used on the QCPort subnetwork is used in this application. Data is arranged in the following manner: Cutler-Hammer EtherNet Products #1-1

2 Table 1 Example Modbus data exchange tables in EMA At the time of writing, CHStudio did not support configuration of the EMA, so it was not possible to change the cover control configuration and data exchange size in a convenient manner, so the defaults were used. The EMA also has an out-of-box configuration which includes a default fixed IP address ( ). Since this is often incompatible with EtherNet subnet masks found on most networks, we will need to change it by placing the EMA into BootP mode. Simply holding down the AC (Auto Configure) button on the EMA while cycling power to it will restore a factory default condition in the EMA (which includes BootP mode). This type of power cycle will also map the cover control data into the EMA and reset the devices on the subnetwork to factory default. At this point, a BootP server is used to assign an IP Address to the EMA. There are many BootP servers available to achieve this task, but familiarity with the Rockwell product made it the server of choice for this test. Once launched, the following screen will appear: Figure 1 Screenshot of Rockwell s BootP Server Cutler-Hammer EtherNet Products #1-2

3 After a short while (may be as long as a minute), the MACID of the EMA will appear in the Request History pane. When it does, simply double click on it and assign the desired address, making sure to pick one that will match the subnet mask of the NOE card in the PLC and any other network device that will access it (such as the computer containing the BootP server). Once this is done, you have successfully assigned a new IP address to the EMA. All that remains to be done is to confirm it using the Windows ping command and then to store the new address in the EMA using the Modbus register access tool ModScan. Here is a refresher on ping : And here is the opening screen for ModScan: Figure 2. The Window s Ping command Figure 3. Screenshot from Win-Tech s Modscan Modbus register tool Cutler-Hammer EtherNet Products #1-3

4 Once connected (Connection Menu) you have access to the Modicon registers. You will also notice that the NS LED on the EMA that until now was flashing, will go solid green. Use the Modbus Point Type pulldown to select Holding registers which is where all of the EMA control, status, and data exchange registers are found. The IP Address mode is found in register Setting it to 3 will save your new address, you will see this value change to 1 soon after indicating a fixed IP is set. Now Modscan can be used to turn the starter on/off by accessing registers (Channel A/B scan) and (the starter control byte). Double-click directly on the registers in the table and a value entry dialog will appear. Place the decimal number 1 in to activate scanning on Channel A (the channel A status light will change from a 25% ON strobe to a 75% ON strobe. The cover control will follow suit. Now for the moment of truth place the decimal number 5 in register which activate the Run and Permissive bits in the Cover Control. Provided the Cover Control is in Auto, the starter will pull in. Figure 4. Screenshot of Modscan with Channel A scan and start/permissive activated You have completed the commisioning on the EMA, now it s time to shift focus to the NOE card in the Quantum. Configuration of the PLC EtherNet Scanner Card Once the card is inserted into the PLC chassis, there is virtually no additional setup to be done on the NOE, other than plugging in it to your hub. All configuration of the NOE is done in the IO Chassis setup in Concept In version 2.5 of Concept, the IO library files for the various flavours of NOE are included and Cutler-Hammer EtherNet Products #1-4

5 there is no need to import them using ModConnect. This may be a required step in earlier versions. The first step is to create a new PLC program from scratch Configuration of the PLC I/O chassis and testing the connection With Concept installed on the programming PC, and a Modbus cable linking the PC to the PLC, launch Concept and create a new project. Launch the Configurator (Configure menu) and setup the PLC type. Notice that with Quantum PLCs (and Modicon PLCs in general) it is possible to configure clocks, battery coils, IO card addresses, etc. to any range within the PLCs available memory map. In this configuration, no real time clocks or battery coils were configured at all since we will not even be programming logic into this processor. Figure 5 Screenshot of PLC Configurator in Concept Cutler-Hammer EtherNet Products #1-5

6 Under the Configure menu, launch IO Map. Figure 6. Screenshot of I/O Map in Concept This screen displays all available drops on the Modicon remote/local IO rack scheme. Since we only have one processor and no remote IO heads, there is only one row available. Click Edit in the far right-hand column. Figure 7. Screenshot of IO rack in Concept The screen that appears is a display of all of the cards and their orientation in the chassis. Here you can also change the range of addresses assigned to each card. Notice that the EtherNet Cutler-Hammer EtherNet Products #1-6

7 scanner does not require addresses to be assigned. This is dealt with in the Ethernet IO Scanner dialog further ahead in this note. Adding IO cards is a simple process of clicking on a slot and selecting the catalog number of the card that is actually installed in that slot. Figure 8. Screenshot of I/O Module Selection Dialog in Concept Adding address ranges from which to write and collect data is done in the Config IO Extensions tree in the PLC Configuration dialog in Concept. Notice that once the card has been added to the chassis, a sub-entry entitled EtherNet IO Scanner appears under Config IO Extensions. Double-click on this entry to expose the following dialog box: Figure 9. Screenshot from IO Scanner dialog in Concept Cutler-Hammer EtherNet Products #1-7

8 The scanner can be assigned an ethernet IP address either via BootP server as we did with the EMA, or by selecting the Specify IP Address radio button and editing the text box with the desired IP. Hitting Go will cause Concept to try and access the Factory Cast web server in the NOE. This version of NOE does not support Factory Cast. Leave the entry as is, as well as the Subnet mask if suitable and proceed to the IO Scanner Configuration table near the bottom of the dialog. Notice it s possible to assign up to 128 slaves to the NOE. Modicon documentation notes that a total of 64 devices can be assigned with a data exchange limitation of 4000 words in and 4000 words out, so use caution when specifying network equipment requirements. Under row 1 in the table, add the IP Address of the EMA. THE UNIT ID MUST MATCH THE MODBUS PORT ADDRESS ASSIGNED ON THE DIP SWITCHES OF THE EMA. Set Health Timeout for 400 ms, and Repetition Rate for 200ms. Read Ref Master is the data starting point to read into in the PLC. Read Ref Slave is where to read from in the EMA. In this example, for convenience (and because there is only one slave) the range of registers in the EMA are mapped into the same range in the PLC. (eg, Read Ref Slave begins at in the EMA, and was mapped to in the PLC). Under row 2 in the table, follow the same example for Write Ref Master and Write Ref Slave. Match the Read Length and Write Length with the actual length of data in the EMA. A description can also be assigned. Note: You can have the reads and writes in the same row. Cutler-Hammer EtherNet Products #1-8

9 Once the IO map and Ethernet scan registers are configured, it is time to send the configuration to the PLC. When an attempt is made to go online to the PLC, you will be prompted to enter the Comm Port Settings. The following screen shows the configuration setup for the test machine 1. Figure 10 Screenshot of PLC Connection dialog in Concept 1 The Quantum has two default modes and one memory setting for Modbus port access. The two default modes are Ascii (2400, 7,E,1) and RTU (9600, 8,E,1). There is an issue with using RTU mode in Concept on NT since NT s Hardware Abstraction Layer (HAL) does not allow low level access to serial ports which is required for RTU handshaking (source: Groupe Schneider Tech Support). Cutler-Hammer EtherNet Products #1-9

10 Figure 11. Screenshot of Reference Data Editor (RDE) in Concept With the configuration loaded in the PLC, simply access the RDE ( Reference Data Editor ) from the Online menu, and access the data register which corresponds to the Input or Output register as configured in the IO scanlist in previous paragraphs. You can now bump the starter on/off using the Reference Data Editor in the same way you used Modscan. Cutler-Hammer EtherNet Products #1-10

11 Glossary Of Terms IP Address Subnetwork MAC ID Ping EtherNet PLC PLC Chassis BootP A network which is attached hierarchically below the main network. Messages from the main network are routed through an adapter to this lower level network. Topology and protocol can differ between the main and subnetwork. A unique identifierstring hardcoded into each EtherNet adaptor. During manufacture. The MAC ID is an alpha-numeric string containing six (hexidecimal) character pairs (one byte each). Network management tool built-into the Windows operating system. Ping is a Command Console utility (DOS) invoked from the Windows Command Line. Typing CMD at in the Run dialog under the Windows Start Menu launces a Command Console. Typing in ping will launch this utility. Programmable Logic Controller The common bus into which PLC cards are inserted in order to provide inter-card communication. Selectable mode for an EtherNet device. Placing an EtherNet device in BootP mode will allow it to receive a new IP Addres from a BootP Server. The EtherNet device then acts as a BootP client to accept this address. Cutler-Hammer EtherNet Products #1-11

12 Appendix 1 D77D-EMA Dipswitch Settings Switch Mode 1 = ASCII 0 = RTU Switches B2, B1 & B0 Switches 1 to 7 Literature Details USE Rev 1.0 Oct 1999 Schneider Electrical 2. MN E Dec 2003 Eaton Electrical 3. MN E Jan 2004 Eaton Electrical Cutler-Hammer EtherNet Products #1-12