Smart UPS overvoltage alarm

[Anonymous user]

Hi,

We have deployed sevaral APC 1500 UPSs in our network with either 9617 or 9630 Network management cards

Some of these UPSs keep generating alerts saying that a high input voltage is receiving to the UPSs.

following are the voltage parameters configured in the UPS

Rated output voltage - 230
High transfer voltage - 253
Low transfer voltage - 208
sensitivity - Medium

According the UPS data log ( attached herewith ), the input voltage is around 250 V but as Checked from a multimeter, the input voltage is always equal to or less than 240 V.
( the difference between the UPS and multimeter readings is around 10 V )

Can someone please let me know the reason for this differenc ?

The alarm clears if I move the High transfer voltage to 257 V.

[Anonymous user]

Hi kumaraw, was this a true RMS volt meter you were taking the readings from? Either way changing the parameter should help with the situation. it is possible that the voltage could have some fluctuations that are causing the ups to trim the voltages closer to 230v. Hope this helps.

[Anonymous user · Accepted solution]

Hi R2,

Thanks for the response.

Yes I measured the voltage using a True RMS multimeter.

Can you elaborate further about the high transfer voltage ?
Which of the following performed by the UPS when the input voltage is equal to the high transfer voltage ?

a. start voltage trimming
b. switch to the battery backup