GE B30 Communications Manual

Also see for b30: Maintenance manual Instruction manual Instruction manual Instruction manual Communications manual

Contents

CHAPTER 2: MODBUS COMMUNICATION MODBUS FUNCTION CODESUR FAMILY – COMMUNICATIONS GUIDE 2-522.2.3 Execute operation (function code 05h)This function code allows the master to perform various operations in the relay. Available operations are shown in thesummary table below.The following table shows the format of the master and slave packets in Modbus RTU. Modbus TCP/IP ADUs have a MBAPinstead of slave address, and CRC is in another stack layer. The example shows a master device requesting the slavedevice 11h (17 decimal) to perform a reset. The high and low code value bytes always have the values “FF” and “00”respectively and are a remnant of the original Modbus definition of this function code.Table 2-6: Master and slave device packet transmission exampleTable 2-7: Summary of operation codes for function 05h2.2.4 Store single setting (function code 06h)This function code allows the master to modify the contents of a single setting register in an relay. The following tableshows the format of the master and slave packets in Modbus RTU. Modbus TCP/IP ADUs have a MBAP instead of slaveaddress, and CRC is in another stack layer. The example shows a master device storing the value 200 at memory mapaddress 4051h to slave device 11h (17 dec).NUMBER OF REGISTERS - high 00 DATA #1 - low 28NUMBER OF REGISTERS - low 03 DATA #2 - high 01CRC - low A7 DATA #2 - low 2CCRC - high 4A DATA #3 - high 00DATA #3 - low 00CRC - low 0DCRC - high 60Master transmission Slave responsePacket format Example (Hex) Packet format Example (Hex)SLAVE ADDRESS 11 SLAVE ADDRESS 11FUNCTION CODE 05 FUNCTION CODE 05OPERATION CODE - high 00 OPERATION CODE - high 00OPERATION CODE - low 01 OPERATION CODE - low 01CODE VALUE - high FF CODE VALUE - high FFCODE VALUE - low 00 CODE VALUE - low 00CRC - low DF CRC - low DFCRC - high 6A CRC - high 6AOperation code(Hex)Definition Description0000 NO OPERATION Does not do anything0001 RESET Performs the same function as the front panel RESET key0005 CLEAR EVENT RECORDS Performs the same function as the front panel CLEAR EVENT RECORDS menucommand0006 CLEAR OSCILLOGRAPHY Clears all oscillography records1000 to 103F VIRTUAL IN 1 to 64 ON/OFF Sets the states of Virtual Inputs 1 to 64 either “ON” or “OFF”Master transmission Slave responsePacket format Example (Hex) Packet format Example (Hex)