modbus serial communication to P342020

[shabeenek]

Good day friends,

Im trying to receive modbus data from a power meter METSEPM5110 to controller P342020 which has serial modbus rj45 port. The meter has D1, D0, C and Shield terminals. 

On the controller side (P342020) RJ45 port, I identified 4 and 5 pins are D1 and D0 respectively and pin 8 is Common. I connected accordingly using a terminal block. 

Using the READ_VAR, I am not receiving data from meter. 

baud rate is set to 9600, parity even

[Bosswaffle]

In Control Expert, did you setup the M340's serial port as a 2 wire RS485 modbus master running at 9600 baud with even parity? Did you change the default speed of the METSEPM5110 from 19200 to 9600? 

If those are both setup then:

1. Try swapping D1 and D0.
2. Try using the serial port on your computer or a USB to serial converter. (via modscan/kepware/topserver/etc.)
3. Post your code here so we can review it.

[shabeenek]

Solved brother. There was 1 offset in the modbus register. When I gave register number one less than in register in read var, data was read.

Thankyou