Problems with APC UPS and/or power

I'm having a weird and annoying issue with an APC smt1500 UPS at a client. Wondering if anyone can give me any tips as APC have not been forthcoming.... This UPS protects all devices at this client: SBS 2011, ADSL modem, firewall, WAP, PBX, switch, USB backup drives etc. The ups has a light load, only around 15% and the monitoring is done on the SBS with PowerChute via USB.

This week I've had 2 graceful shutdowns initiated by the ups, when the client comes in, the trip switch for the server room has tripped - flipping it back and everything comes back on as expected. No problem. On further examination of logs, the mains voltage has been high before the switch to battery. Around 252v. The ups had been trimming throughout the evening.

I've also had 1 non graceful shutdown where all devices appeared to have lost power entirely, without the UPS kicking to battery. Again the client states that the trip to the the server room had been activated, but for some reason, the ups didn't switch to battery and the devices lost power instantly. This is confirmed in the windows logs. Very annoying.

This loss of power without the battery kicking in has happened around 5 times in a year and I'm at a loss to understand why. I'm remote to the client so am very rarely on site (150 miles away), so I have not been able to see the aftermath of one of these occurrences myself. They have all happened in the evening or overnight and have all been preceded by high transfer voltage prior to the loss. The UPS is only a year old and the self tests pass weekly.

I have a feeling that it is a combination of a weird trip switch, high line voltage and something odd in the ups...

Any tips welcome.

That is a lot of stuff to be running off one UPS.

Can the UPS be plugged into another phase, or a different socket on a different ring?

If not get a sparky in to check the breaker etc

Out of curiosity any where Newcastle or the North East? Had that before, turns out the power is unreliable. Brownouts with the occasional spike afterwards. The spike after a brownout on some UPSs would not switch to battery.

Could be internal wiring or the breaker.

Get them to have a sparky look at the power. You can also change the sensitivity in the powerchute settings. Had a similar UPS problem on a site and it turned out to be the power supply to the room.

We've had issues with the bigger APC units doing similar things if they haven't had a run time calibration done, it seems they sometimes get confused and think there isn't enough battery to support the load and shut down. IIRC the recommendation was to do a calibration at least once a year and definitely do one when the unit is installed (ideally with about a 30% load on).

Thanks guys for your tips.

Had another drop last night - no email warnings from the unit - all the devices lost power at the same time. The client says that the unit was continuously beeping when she arrived and the following error message was displayed on the unit:

FAULT STATE: AVR Relay Weld, call Tech.

The breaker hadn't tripped this time either. From a quick google, sounds a like a problematic UPS - people are also suggesting that this fault state occurs when the unit has been trimming or boosting and isn't able to switch back correctly. The unit was trimming when the drop occurred. I have also suggested getting an electrician to check over the power to the room.

To answer some questions: sadly no other outlet socket in that room and no the UPS had never been calibrated. I'm in contact with APC as we speak.

I will report back on the outcome.

Just to come back on this: APC are sending an RMA replacement for this UPS - so some good news.

I have also advised the client to get the circuits/breakers checked as well.