APC NetworkAIR FM-40 - Off Line, Mains Failure

[Anonymous user]

Dear Experts,

My customer is facing problem with their APC NetworkAIR FM-40 CRACK.

They have 2 units running in N+1 config. At the moment, backup unit is still running but very unstable. Engineers suspect blower is about to give up.

As for the primary unit, engineers are still trying to pin point the part or module that's causing this problem. Error message is Mains A & B Failure.

Enclosed herewith are some screenshots & event logs extracted from the unit. Urgently need help & opinion.

We've checked mains breaker at the CRACK and input power is within range.

[BillP]

L2SupportServices-Cooling - is this something that you could assist with please? Thanks!

[BillP]

Hello. The Mains A and B Failures come from two boards that monitor the main power coming in and the control voltages off the transformers. First check the transformers to make sure they have 24 volts between the red and black wires and 30 volts between the yellow and black wires on the transformers. If one of the transformers is bad, check for shorts in the unit before replacing it to make sure the new transformer is not bad. If the transformers are good. Check the line voltage coming into the Mains A board on connections 94-95-96. Make sure you have the appropriate voltages there. Check all the fuse blocks to make sure a fuse has not blown somewhere in the unit. If no faults are found, it would be best to call into the local tech support to get further troubleshooting to get live direction while with the unit.

Thank you

[Anonymous user]

Dear L2Support,

Thanks that's very helpful. At least now we know what & where to look for faults.

Going over with local tech today. I will try out your methods.

[Anonymous user · Accepted solution]

HI

I'm facing same problem . Did you find any other solutions ??