Smart UPS 1400 (SU1400RMNET) Nominal Battery Voltage

[fettinger_apc]

This was originally posted on APC forums on 11/16/2011

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I recently received a Smart UPS the university was recycling. It seams to have some issues but I would like to restore it if possible. The unit came with batteries, but they are unmarked and unlabelled. I was wondering what is the fully charged nominal voltage of the battery pack (RBC8). I noticed there are 4 batteries in a series/parallel combination, which leads me to believe it should be 24V, but I wanted to be sure before ruling this out as a potential cause to the problem.

To clarify, what should the voltage read if I were to measure the contacts connected to the board itself, leading to the batteries?

[fettinger_apc]

This was originally posted on APC forums on 11/17/2011

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Thanks for the help with the battery voltage.

On this unit, (Board 640-0732H Rev 8 Copyright 1996), what goes between jumpers labelled W3 and W4. On the reverse side, it is labelled RY5?

If it is not proprietary information, does anybody have a copy of the circuit/board layout diagram for this board? This would really help me isolate the root cause.

Thanks.

[BillP]

This reply was originally posted by Dakota on APC forums on 11/18/2011

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APC won't give diagrams but what is the ups doing???

[fettinger_apc]

This was originally posted on APC forums on 11/18/2011

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It is not starting up correctly.
I have measured 120VAC across W3 and W4.
If anybody has the similar model, could you take a look inside and tell me what is suppose to be there.

Thanks

[BillP · Accepted solution]

This reply was originally posted by Dakota on APC forums on 11/17/2011

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24 Volts Is Acceptable But Low For APC Ups

The batteries fully charged should be at 27.5 Volts