BE750G shuts down unit on self-test

[BillP]

Bought a new Dell Pentium Dual core with XP Pro, House lights flickered, Belkin UPS didn't stop unit from shutting down. Figgured unit didn't have the watts for new unit. Belkin UPS had worked with previous unit. Ordered new BE750G after using APC's "make sure you have the right unit for your power needs" helper.
Followed APC's instructions to set up, left unit on for 48 hours, used the hibernation mode, worked fine. Bought PC back up and read a little. Tried to do the self test. Shut system down (pc). Waited five minutes and rebooted. Tried it again, same thing.
Read the forums here for the last two hours, did not see this issue. Yes, it shows the APC in the device manager, no, there is no unrecgonized USB connections. In the APC Powerchute PE, it shows that the self-test has never been run. Unit shows to be using 54 watts of the power available.

Any clue?

[BillP]

Does not have this problem with a different computer hooked up to it. Looks like Dell has made their unit just a little too close to the edge. Will try to contact Dell with issue. I must be the only person in the world with this issue, or no one else is concerned with it. Thanks for the suggestions.

[BillP]

do you have any other load that you can test this with besides the computer? or is there anything else plugged in to a battery back up outlet thats NOT turning off? is the UPS itself turning off as well when you do this test?

to test this, you could leave the computer attached via USB to monitor what happens but power the PC via the wall or some other source. then maybe plug in a lamp or something to one of the battery back up outlets and initiate a self test and see what happens. this unit outputs a step approximated sine wave on battery that some higher end computers may not like, especially if they have dell "super efficient" power supplies.

[BillP]

Good thoughts, let me try this. I have the boss's (spouse) PC on a different UPS. I'll plug her's in to the 750 and put my in the wall and see what happens to hers on the self test. I have a Netgear Wireless Router, but I did not think to look at it. thanks, I'll try this. I really believe it may be the Dell, but I know when I hit Dell, the issue will be "anywhere but Dell," till proven exhaustively otherwise!

[BillP · Accepted solution]

no problem. it seems like the power supply in the computer does not like the step approximated sinewave output of the Back UPS while on battery or even maybe the transfer time TO battery, which is 4-6ms. you'd need to look into a UPS with a pure sinvewave output most likely and/or a shorter transfer time to battery, such as a Smart UPS.