Modbus Ethernet

[intersyn]

All,

I am attempting to connect to a baldor H2 inverter drive via modbus over Ethernet. I have verified proper setup of the drive and comms with my computer using modbus poll freeware(Tx and Rx with no errors). I set up a modbus sever under "my Computer"(input modbus slave IP address) and believe i used the right "coils"(from baldor comms book) to try to simply read coils from the drive. I get DSC module errors

1967353902

The Modbus I/O server failed to receive any response from the Modbus slave device. Ensure that the Modbus slave device works properly and that the connection between the Modbus master and slave devices is configured correctly.

AND

−1967353907

The Modbus I/O server failed to communicate with the Modbus slave device. Ensure that the Modbus slave device works properly.

I am sure this can be fixed, but I don't know how 🙂

Regards,

Doug Schaaf

[S1ack]

I stopped using the Modbus server a while ago, and started using the Modbus function block library (more control).

You might try a quick test with those blocks to see if makes a difference.

One thing that can cause problems for Modbus Ethernet is the Unit ID: I see no way to specify it on the I/O Server, and do not know what Unit ID the I/O server uses. We've seen some instruments that require a non zero unit ID.

[intersyn]

I have downloaded the modbus library, is that what you are refering to? 

[S1ack]

Yes