GE 469 Communications Manual

Also see for Masoneilan 469 Series: Instruction manual Instruction manual Instruction manual Instruction manual Instruction manual

COMMUNICATIONS GUIDE MODBUS FUNCTIONS469 MOTOR MANAGEMENT RELAY – COMMUNICATIONS GUIDE 5Modbus FunctionsSupported FunctionsThe following functions are supported by the 469:Modbus Function Code 01: Read Relay CoilModbus Function Code 02: Read Digital Input StatusModbus Function Code 03: Read Setpoints and Actual ValuesModbus Function Code 04: Read Setpoints and Actual ValuesModbus Function Code 05: Execute OperationModbus Function Code 06: Store Single SetpointModbus Function Code 07: Read Device StatusModbus Function Code 08: Loopback TestModbus Function Code 16: Store Multiple SetpointsRead Relay Coil / Digital Input StatusModbus implementation: Read Coil and Input Status469 Implementation: Read Relay Coil and Digital Input StatusFor the 469 implementation of Modbus, these commands can be used to read Relay CoilStatus or Digital Input Status.MESSAGE FORMAT AND EXAMPLE, FUNCTION 01:The standard implementation requires the following: slave address (one byte), functioncode (one byte), starting relay coil (two bytes), number of coils to read (two bytes), and CRC(two bytes). The slave response is the slave address (one byte), function code (one byte),relay coil mask byte count (one byte; always 01 since only six relay coils), bit maskindicating the status of requested relay coils (one byte), and CRC (two bytes).Request slave 11 to respond with status of relay coil 3 to 5:Relay Status1 TRIP Energized2 AUXILIARY De-energized3 AUXILIARY De-energized4 ALARM De-energized5 BLOCK START Energized6 SERVCE EnergizedBit Mask 0011 0001 (0 × 31)Master Transmission Bytes Example DescriptionSlave Address 1 0B message for slave 11Function Code 1 01 read relay coil statusStarting Relay Coil 2 00 03 starting relay coil 3Number of Relays 2 00 03 3 relay coils (relays 3 AUXILIARY,4 AUXILIARY, and 5 BLOCK START)CRC 2 8C A1 computed CRC error codeSlave Response Bytes Example DescriptionSlave Address 1 0B message from slave 11