Apc Backup pro 1000 running on battery when apartment generator power is on

[kaustubh123_apc]

This was originally posted on APC forums on 3/18/2014

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Hi I have a apc backup pro 1000 connected to my computer for backup. The apartment complex I live in has a power generator but my apc ups switches to using battery when the generator is active. The input voltage on the ups display is 217-218 volts at 47 hz when the generator is active. I have tried switching the ups sensitivity to low but it still run on battery. Can someone please explain why when everything in cluding my tv and fridge run normally  when the generator is active but the ups switches to using its reserve battery instead.

Thanks

[Battman_apc]

This was originally posted on APC forums on 3/18/2014

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Hello, from your profile it appears you are located in India - but it would help to know for your exact area what normal voltage and frequency of the power in your building ? Thanks.

[BillP]

This reply was originally posted by Joe on APC forums on 3/19/2014

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Although the generator may be indicating appropriate output voltage level and frequency, other aspects of the waveform itself, such as heavy distortion, etc, would still be unacceptable to the UPS which would continue to remain on battery.

[kaustubh123_apc]

This was originally posted on APC forums on 3/19/2014

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Hi , yes I am in the banglore city in india and the normal power voltage is 238-240 volts at 50 hz. Currently my building is running on the generator for the past 14 hours due to a fault in the main electical line. Since my ups troes to run on the battery for when the generator is active it has shut down a couple of imes but if I turn it on after a few hours later the battery is fully charged again. So it is receving charge when on the generator power but still uses the battery when turned on

[kaustubh123_apc]

This was originally posted on APC forums on 3/19/2014

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Hi if it is the waveform distortion distortion causing the ups to use its battery is there a way to detect such a issue. Currently as I stated in the op all other equipment in the house including the fridge and tv seem to be operating normally on the generator power but the ups does not . The power and frequency inputs which display on the ups also do not vary over time. So the generator power seems to be stable at 217-218 volts at 47hz.

[BillP · Accepted solution]

This reply was originally posted by Joe on APC forums on 3/19/2014

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Specialized test equipment, such as a power line monitor, would be able to detect such distortion if present.  I am not sure about your specific UPS, but most of them have the ability to create an event log that may be able to capture the reason that it continues to remain on battery power.

I am assuming that the generator in your building takes at least several seconds to pick up the load after a power failure and total loss of power is the reason that your UPS kicks in.  It may be possible to restart your UPS during the time the building is on emergency power and then check the event log for possible reasons it refuses to transition to building AC power.