Beginner Communication question.

How do Allen Bradley Prosoft Modbus plus communicate with Modicon PLCs? Are they connected some way just by wire or wireless communication?

Modbus Plus is a proprietary network and requries a specific two-conductor shielded cable and specific connectors.

The big reference manual for Modbus Plus can be downloaded from Schneider:

http://www.schneider-electric.cn/downloads//85257689000007EE/All/B1F7510F1A29DD46852576B2006B5A17/$File/40-Modicon-EN.pdf

Thanks! I will check it out. So far I figured out they communicate through a Modicon Brdige/Mux NW-BM85-000. I just cant physically locate the device. thanks for your help.