Ever since EMC (utility company) put in a digital electrical meter at my home, I've been having a surge to my UPS units.
I have completely replaced my entire electrical panel (it needed it).
EMC has upgraded my tranformer from a 10K up to a 25K.
Yet, every 8 hours, when the meter is taking a reading it trips all my UPS units in my home. (I am a computer consultant and have several machines here). It doesn't trip them but for a moment and it does what I call, 'clicks' 4 to 6 times where the indicator goes from ready to trouble then it stops.
I have a monitor that detects the UPS alarms and it is not getting to a brown-out stage, just a momentary disconnect is indicated.
I am at my WITS end with this. Any suggestions or help would be greatly appreciated.

Thanks!
Gunilupis

Your UPS will transfer to battery whenever the power line is out of tolerance. This could be low voltage, no voltage, high voltage, or frequency out of tolerance.

The only way to determine what the real cause is would involve connecting a metering devie to the power line at one of the UPS units.

If you have or can borrow a digital multi meter that can record high, low and average readings, you can start by checking the voltage & see what is happening when the UPS transfers. If voltage isn't the problem, then you could set the meter to record frequency & see if that is the cause.

Next step would be to rent and connect a power line analyzer & have an engineer familiar with power line disturbances analyze the readings.

You might try the following link to see if APC has any info on this exact problem.

http://www.apc.com/support/index.cfm

Yes, thanks for that information, however, the tripping is caused whever the meter takes a reading, they have put a monitor on at the outside meter and it shows that things are within tolerance. It was at the low end which is why they put in the 25k transformer, but it still happens...
I will be contacting APC though to see if they have any suggestions...but I'm still open to anything else I might be able to do.

Thanks!
Gunilupis

Taking a reading outside at the meter is not the same thing as taking a reading at the outlet the UPS is plugged into. A UPS does not transfer to backup power for no reason and the only readings that would matter would be at the outlet.

With any luck, APC may have heard of this problem and will be able to give you some guidance.

Good luck & if you do find a solution or an exact cause of the problem, please post it here as I'm always curious about these types of problems.

Tom