Control Logix PLC Redundant Power Supply


Thread Starter

Mark Riche

Does anyone have experience with the Allen Bradley Control Logix PLC redundant power supply setup? Is it worth the cost? Is the adapter reliable or a more likely single point of failure?

This is opinion only so take it for what its worth... the MTBF for power supples is so much greater than for typical logic processors I don't see the advantage. This is except for having a 2nd power source from a reliable place (think UPS) where that may make some sense in a particular application.

I had some old data that showed a MTBF of over 100,000 hours on a PS while the processor was at 35,000 hours. I'm sure that is improved in the last 10 years. Also, my experience says that failures are much more likely due to software errors and that is not made better with redundant processors.

If I were to put money into redundancy, it woudl be at the I/O level where the stress on modules is much greater.