ML1400 channel 2 modbus port pinout

I have a project which i will need to use both comm ports as modbus rtu master. I purchased a 1763-nc01 for the mini din connector(channel 0) but would like to use the 9 pin serial connector(channel 2).


thanks

Channel 2 is an ordinary RS-232 "DTE" type serial port, so you can use any ordinary serial cable.

The minimum pinout is Pin 2 (RX), Pin 3 (TX) and Pin 5 (GND).

I got the serial port to work. The problem is the application both work on channel 0 perfectly but only has issues when using channel 2. The only difference i see is channel 0 will let me change the protocol to no handshaking 485 network. but channel 2 does not have that same option.

The application is
channel 0
modbus controlled solid state relay for lighting.
19200 even 8 data bit 1 stop bit

channel 2
modbus controlled thermostats for gas heaters in the plant. adjusts the setpoint depending on if the plant is occupied.
19200 none 8 data bit 1 stop bit

Any ideas.

thanks

If channel 2 is connected to a RS485 network then you will probably have to use a RS232 to RS485 converter.

The 232 to 485 converter worked perfectly. Thanks for the information.

2004sk4 said:

The 232 to 485 converter worked perfectly. Thanks for the information.

Click to expand...

Good to hear.

What brand,make and model converter did you use?