There are two devices:
- Eaton EM20/M
(~like Northern Design Cube 400)
- Volison ADM-5850G
Connected them like:
Trying to get data from EM20/M which supports ModbusRTU(RS-485) protocol using ADM-5850G converter ModbusTCP<>ModbusRTU.
Converter(ADM-5850G) and Slave(EM20/M) are set for 9600 baud rate.
Also, the converter's settings:
Some EM20/M's programming pages:
Created a packet containing
00 01 00 00 00 06 01 03 9e 42 00 01 which should read 1 register at address 40515 from EM20/M which Slave ID is 1. Register's address got from references below(links).
Sent same packet using two tools(wireshark shows same result for both tools):
modpoll -a 1 -r 40515 -c 1 -1 192.168.1.104 -l 1000 -o 0.5
echo -en "\x00\x01\x00\x00\x00\x06\x01\x03\x9e\x42\x00\x01" | nc -w 1 192.168.1.104 502
A "Cmd" on EM20/M led blinks one time after command having being sent and there's no response:
1 modpoll program outputs:
- 2 netcat just outputs nothing
Why is there no response?
Do we send a valid packet(also, note that "Cmd" led blinks shortly on EM20/M after command sent)?
- ModbusTCP: http://www.simplymodbus.ca/TCP.htm
- EM20/M manual we didn't find, but found Cube 400's: https://www.ndmeter.co.uk/brochures/Manuals/Cube%20400%20Manuals.zip