Recently, when connected to a Quantum PLC via Modbus I get the following error when trying to download a configuration or program:

User not logged in, Error - OL9-1600

However, to be able to download to the PLC I have to be connected, but the error says I'm not!!!

I can download OK via Modbus+... Any help is appreciated.

Damon

 

This could be the problem of your Modbus cable.
Please change your Modbus cable and proceed.

pl reply after trying the same.

 

Problem solved, turned out to be a faulty programming lead.

Thanks.

Damon