PMEPXM0100 in redundant M580 PAC

[EthanB]

Dear Schneider Electric Community,

I am seeking clarification on Profibus DP device accessibility in a redundant M580 PAC architecture, as depicted in the attached diagram. For clarity, the RIO ring and HMI connections are not shown, focusing solely on the Profibus DP network.

My M580 PAC system utilizes redundant PMEPXM0100 Profibus DP Master modules, each located in its respective Main and Standby rack, connected to a chain of Profibus DP devices.

Could you please elaborate on which Profibus devices (PB Device 1, 2, 3, or 4) would remain accessible to the M580 PAC in the following specific failure scenarios:

1. The PMEPXM0100 module in the Main M580 rack fails (as indicated by "1" in the diagram).

2. The Profibus DP cable between PB Device 2 and PB Device 3 breaks (as indicated by "2" in the diagram)

Any insights, explanations of the failover mechanisms, or specific configurations that influence these behaviors would be greatly appreciated.

[Trinxs1 · Accepted solution]

The M580 hot standby system will not swap automatically if the master Profibus module fails.  Generally you have to manage the first section of logic so that it monitors the status of both master modules and if the module fails that is in the primary CPU rack and the other CPU rack is OK you should write logic to change standby to primary.

With respect to a cable break I assume that you will not have communications as the cable is no longer terminated.   There are various network devices that break the cable into sub spurs so that if a device fails or a local cable fails the effect is limited to one small area.