Each Magnum bridge can manage a single inverter-charger. Both devices are needed. These two units translate messages from the Magnum-format to RV-C so all devices, any, can see the info, at will.
That said, they don't replace the TM102. Thats a data collector for everything from holding tanks to transfer switch. It starts and stops the genny and can monitor a raft of house features. So, its not in contention today.
The can-bus wires from the TM502s each connect to the RVC bus. Each will also need power.
At this point, we'll need to discuss which connectors those units were ordered with so we can assist in the final connections. A phone conversation is needed at this point to gather the best quality details. That should speed this along.