A phase synchronization fault exists.

[Anonymous user]

I have a site with an MGE Galaxy 3500 10 kVA, there is also a backup generator for the location.
When they loose power and the generator starts I get the following messages on the UPS:
10/21/2012 18:47:23 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
10/21/2012 18:47:08 UPS: No longer on battery power.
10/21/2012 18:47:03 UPS: An input voltage or frequency problem prevents switching to bypass mode.
10/21/2012 18:47:03 UPS: On battery power in response to an input power problem.
10/21/2012 18:42:56 UPS: A phase synchronization fault no longer exists.
10/21/2012 18:42:56 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
10/21/2012 18:42:35 UPS: A phase synchronization fault exists.
10/21/2012 18:42:35 UPS: No longer on battery power.
10/21/2012 18:42:27 UPS: On battery power in response to an input power problem.
10/21/2012 18:42:25 UPS: An input voltage or frequency problem prevents switching to bypass mode.
Is there an issue with the power being supplied from the generator?

[Anonymous user · Accepted solution]

Sorry it didn't added the subject:
10/21/2012 18:47:23 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
10/21/2012 18:47:08 UPS: No longer on battery power.
10/21/2012 18:47:03 UPS: An input voltage or frequency problem prevents switching to bypass mode.
10/21/2012 18:47:03 UPS: On battery power in response to an input power problem.
10/21/2012 18:42:56 UPS: A phase synchronization fault no longer exists.
10/21/2012 18:42:56 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
10/21/2012 18:42:35 UPS: A phase synchronization fault exists.
10/21/2012 18:42:35 UPS: No longer on battery power.
10/21/2012 18:42:27 UPS: On battery power in response to an input power problem.
10/21/2012 18:42:25 UPS: An input voltage or frequency problem prevents switching to bypass mode.

[BillP]

yes, thats what it sounds like, especially since the fault happens with the generator. do you have the data log for that time period too? sounds like the three phases are out of sync.

[Anonymous user]

Yes I have attached the data log.

[BillP]

i had someone more experienced with this UPS take a look at the issue.

One thing we would like to know is if the items reported by the NMC between 18:42 and 18:47 are when the generator was running. These events could be a result of a utility failure but they could also be the same events if the UPS does not like the generator output.The G3500 has a maximum slew rate of 1Hz/s. Slew rate is how fast the output voltage is allowed to change. So if the UPS is having difficulty tracking the input waveform, (if it is changing faster than 1 Hz/s) then the UPS will not be able to synch to mains. If this is a single mains UPS (they almost always are) then the bypass and the mains are the same input. Therefore, the UPS can't sync to bypass either.

So the UPS goes to battery until the input waveform clears up. This is typical behavior for small, highly loaded or old generators, or huge generators that have very little load on them.

if you have any further issues or this does not seem correct, it was suggested that you contact our 3 phase power team for further assistance.