firmware upgradation of controlnet module

we have purchased two rockwell control net module 1756CNR/C version -25 but it not work at two controller syn condition. In one controller already existent module version 20 installed and still working but both controllers not synchronised when new module installed in other controller because lower version module require firmware up gradation.

Also i unable to upgrade 1756 CNR/B control net module 20 version. Please help me to resolve the problem

Series A & B firmware can not be upgraded to C. Why don't you install both 1756-CN2R/C? You'll need to modify the declared firmware on your RSLogix project and re-schedule the network (using RsNetworx).

Welcome to the Forum !

It sounds from your post like you are using ControlLogix Redundancy, which has very specific firmware and hardware compatibility requirements. You absolutely must follow the detailed instructions in the release notes for your specific redundancy firmware bundle.

As mentioned, the Series C hardware for the 1756-CN2R module supports only firmware written for the Series C hardware.

Likewise, older Series A and Series B modules cannot be loaded with firmware that only runs on Series C.

If this is a system that is critical enough to need ControlLogix Redundancy, I strongly recommend that you get experienced local assistance. Rockwell Automation has multiple distributors in India who can help you get in touch with the right integrator, technical support, or sales office.