Contents 1. Introduction ............................4 1.1. Specifications ........................... 7 1.2. Dimensions ..........................8 1.3. Appearance..........................9 2. Configuration ............................ 13 2.1. Assigning an IP address to MDC‐700 ..................14 2.2. Editing the config.csv file ....................... 16 2.3. Importing/exporting the config.csv file................. 21 3.4. Connecting to the Web HMI ....................23 3. Troubleshooting ..........................26 4. FAQ..............................29 Q1: What are the maximum numbers of polling definition and local register?......29 Q2: What is the maximum number of registers can be accessed in one Modbus command?..29 Q3: How are the local registers mapped to the polled data in a MDC‐700?........ 30 Q4: How to write data to output channels on a Modbus RTU slave device?....... 32 Q5: How to read the status of each connection? ................. 33 Revision History ............................
1.1. Specifications MDC‐711 MDC‐714 MDC‐741 Ethernet Port x1, 10/100 Base‐TX Protocol Modbus/TCP Slave Max. Connection 8 COM Port RS‐232 x1, (TXD, RXD, RTS, CTS, GND) x4, (TXD, RXD, RTS, CTS, GND) RS‐485 x1, (Data+, Data‐) x4, (Data+, Data‐) x1, (Data+, Data‐) Baud Rate 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 (bps) Data Format N81, E81, O81 Protocol Modbus RTU Master Max. Node 32 nodes for each RS‐485 port Polling Definition 240 definitions for all RS‐232/485 ports Shared Memory 9600 registers for each of AI, AO, DI and DO Data System System 5‐Digit 7 Segment LED Yes, to display IP address Display System LED Indicator Yes, to display heartbeat Mechanical ...
1.3. Appearance Connectors: (For MDC‐714/MDC714) COM3 COM4 COM5 LED Indicator Configuration Display Connectors: Power COM2 Reset Ethernet Port COM1 LED Indicator The LED is used as a heartbeat indicator and slows to approximately one flash per second. Ethernet Port The MDC‐700 is equipped with a RJ45 port for Ethernet LAN connection. When 100BASE‐TX is operating, the 10/100M LED is lit orange. When 10BASE‐T is operating or the machine is ...
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Power Connector Configuration Display MDC‐700 includes a 5‐digit 7‐Segment LED display to indicate configuration in a module as below: The IP address for the MDC‐700 11111. (192.168.255.1) 1. 192 2. 168 ...
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Reset Shorting the RESET pin to GND pin over 3 seconds can reset the IP/Subnet Mask/Gateway addresses to the factory default settings. RS‐232 Wiring 3‐wire Connection Wiring 5‐wire Connection Wiring ...
2. Configuration The necessary configuration for Modbus TCP communication, Modbus RTU communication and polling definition is handled by a single file named “config.csv”. Just follow the easy‐to‐use format defined in the config.csv file and import the new config.csv file via a simple mouse‐click on the main page of the MDC‐700, the data on those Modbus RTU slave devices can be accessed over an Ethernet. Only the Function code 01/02/03/04 can be used in the config.csv file: 01: Read Coil Status (Read DO) 02: Read Input Status (Read DI) 03: Read Holding Registers (Read AO) 04: Read Input Registers (Read AI) If you would like to write data to a digital or analog output channel on a Modbus RTU slave device, the output channel needs be mapped with a local register address in the MDC‐700 by editing the polling definition with using corresponding read function code (01 or 03). Refer to Q4 in the 4. FAQ section for more detailed information. The following section will help you to set up your MDC‐700 module, and show you how to use the web interface to obtain configuration and other information related to the MDC module and associated slave devices. Basic operating procedure Step 1: Assign a valid IP address to the MDC‐700. Step 2: Edit the config.csv file. Note that before editing this file, you should confirm the parameter value for any associated Slave devices. Step 3: Upload the config.csv file to the MDC module. ...
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Modbus Connection The Modbus Connection section is used to configure the Modbus ID of the MDC module and the TCP/IP Port number for Modbus TCP communication. # TCPPort ModbusID * 502 TCPPort: Defines the TCP/IP Port number, in the example set to 502. ModbusID: Defines the Modbus ID of the MDC module, in the example set to 1. Module Information The Module Information section is used to record relative information for the MDC module. It will be displayed on the main page of the MDC‐700, and can be used to one MDC module from the others. # ModuleInfo * this is my data concentrator ModuleInfo: Define the relative information for the MDC module. The string constant has a maximum length of 32 characters. ...
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COM Port Configuration The COM Port Configuration is used to configure the parameters for the RS‐485 Modbus communication connection between the MDC module and the RTU slave devices. # ComPortNo BaudRate DataBit Parity StopBit Timeout PollDelay OperatingMode * 1 115200 8 20 Master * 2 115200 8 20 Master * 3 115200 8 20 Master * 4 115200 8 20 Master * 5 115200 ...
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Polling Definition The Polling Definition is used to define Modbus commands to read data from the slave devices. Before attempting to configure the parameters for the Polling Definition, be sure to check the Com port number that the target device is connected to, the Modbus ID setting for the target device, and the function code, start address, and the quantity for reading data. # UseComPort SlaveModbusID FunctionCode RegStartAddr RegCount * 1 1 * 1 1 * 2 2 * 3 3 * 4 4 * 5 5 Each Polling Definition consists of 6 parameters listed as below: # Defines the type for a polling definition. In the MDC‐700, it provides three types: “*”: Asterisk symbol means that this is a valid polling definition. The MDC‐700 will assign local register for data defined in the definition and save the polled data to the mapping local register. “‐”: Minus sign means that this is a disabled polling definition. The MDC‐700 will assign local register for data defined in the definition but will not poll data. ...
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Introduction to the Web HMI After connecting to the website, the following information will be displayed. # TCPPort ModbusID * 502 # ModuleInfo * this is my data concentrator # ComPortNo BaudRate 1 115200 2 115200 Module Information The Module Information section of the page provides the module information about the MDC module. ...
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The State of Connection When the state is shown as , it indicates that the connection was successfully established and GOOD the parameter settings are valid. When the state is shown as , it indicates that the attempted connection has failed. To TIMEOUT resolve this issue, check whether the parameters listed below match the settings of the RTU slave device. Baud Rate Slave Address Data Format (Data Bit, Parity and Stop Bit) When the state is shown as , it indicates that the connection was ERROR: ILLEGAL FUNCTION successfully established, but the parameter is invalid. To resolve this issue, check whether the Function Code listed in the Polling Definition match the settings of the Modbus RTU slave device. When the state is shown as , it indicates that the connection was ERROR: ILLEGAL DATA VALUE successfully established, but one or more of the parameters are invalid. To resolve this issue, check whether the Start Address of Register and Count of Register listed in the Polling Definition match the settings of the Modbus RTU slave device. ...
3. Troubleshooting In this chapter, we will explain how to troubleshoot the communication problems. Possible causes of TIMEOUT Situation #1: The slave device is not turned on or the transfer function of the slave site may fail. Solution: Check the slave device is powered up and the communication function is enabled. Situation #2: The COM port number to which the slave device is connected is not the same with the UseComPort setting in the polling definition. Solution: Connect the slave device to the COM port number that is defined in the polling definition, or fix the UseComPort parameter to the virtual COM port number that the slave device is connected to. Situation #3: The wiring for communication is wrong. Solution: Exchange the D+ and D‐ wiring of RS‐485 connection, or exchange the Rx and Tx wiring of RS‐232 connection, and check the GND wiring is correct between the slave device and the MDC‐700 module. Situation #4: The Baud Rate or/and Data Format settings in the polling definition are incorrect. Solution: Check and fix the difference of the Baud Rate and Data Format settings between the polling definition and the slave device. ComPortNo BaudRate DataBit Parity StopBit Timeout PollDelay Operating Mode 1 9600 8 100 Master 2 9600 8 3000 1000 ...
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Situation #5: The ID for the slave device is not correct in the polling definition. Solution: Check and fix the difference of ID number between the polling definition and the slave device. Situation #6: The Timeout or PollDelay setting is not long enough. Solution: Lengthen the Timeout or PollDelay setting until it is suitable for communication with the slave device. ComPortNo BaudRate DataBit Parity StopBit Timeout PollDelay Operating Mode 1 9600 8 100 Master 2 9600 8 3000 1000 Master 3 9600 8 3000 1000 Master 4 9600 8 100 Master 5 9600 8 ...
Q3: How are the local registers mapped to the polled data in a MDC‐700? A3: Only the function code 01/02/03/04 can be used in the polling definition section in config.csv file. 01: Read Coil Status (Read DO) 02: Read Input Status (Read DI) 03: Read Holding Registers (Read AO) 04: Read Input Registers (Read AI) Refer to the example below, UseComPort SlaveModbusID FunctionCode RegStartAddr RegCount 1 1 8 1 1 8 2 1 4 2 2 4 2 3 4 2 4 4 The MDC‐700 will sort the order of polling data by COM port number and the sequence of polling definition; and then map the local registers corresponding to the data type (DI/DO/AI/AO) by the order of polling data. So the data comes from different slave devices with ...
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The local registers mapping is listed on the main page of the MDC‐700 module. The MDC‐700 allows users to enable/disable a polling definition by changing the first field of the polling definition section in the config.csv file. There are three types that users can use: “*”: Asterisk symbol means that this is a valid polling definition. The MDC‐700 will assign local register for data defined in the definition and save the polled data to the mapping local register. “‐”: Minus sign means that this is a disabled polling definition. The MDC‐700 will assign local register for data defined in the definition but will not poll the data. “”: Empty means that this is a null polling definition. The MDC‐700 will neither assign local register for data defined in the definition nor poll data. # UseComPort SlaveModbusID FunctionCode RegStartAddr RegCount * 1 0 8 * 1 0 ...
Q4: How to write data to output channels on a Modbus RTU slave device? A4: Step 1: Edit the polling definition for the output channels with read function code in the config.csv file. (For example, use 01 to read DO channels, 03 to read AO channels) UseComPort SlaveModbusID FunctionCode RegStartAddr RegCount 1 1 8 1 1 8 2 1 4 2 2 4 2 3 4 2 4 4 Step 2: Import the config.csv file into the MDC‐700, wait the MDC‐700 reboot in 5 seconds, and then check the addresses for the local registers mapped to the output channels. Step 3: Write data with corresponding function code (05/06/15/16) on your Modbus master device to the local registers mapped for the output channels, the MDC‐700 will process writing operations to the slave devices. ...
Q5: How to read the status of each connection? A5: The status for each connection is saved in the sequence of polling definition from local register address 39600. The maximum number of polling definition in the config.csv file is 240, so the available address for the connection status is from 39600 to 39839. A Modbus master use function code 04 to read the status, up to 126 register of status can be read in one command. For example, the status of the graph shown above is presented as the third column in the following table. Def. number Address Status Status display on web page Def.#001 39600 0 GOOD Def.#002 39601 0 GOOD Def.#003 39602 0xFFFF TIMEOUT Def.#004 39603 0x8201 ERROR: ILLEGAL FUNCTION Def.#005 39604 0 GOOD Def.#006 39605 ...
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