Dell PC does not operate on battery power from Back-UPS ES 750

[Anonymous user]

Just purchased a new Back-UPS ES 750. When I run a self-test the computer restarts. When I pull the power cord from the UPS to the wall to run on battery, the PC shuts down, the light in the PC power button starts a rapid blink in orange (normal on is solid white), the external hard drive plugged into the PC blinks on-off-on .., the optical disk trys to spin up repeatedly at about the same frequency as the power on light is flashing. I also have the PC monitor and a cable modem plugged into the battery back-up outlets on the UPS. They remain powered and act normally. Is there anything I can adjust on the PC to make it operate properly?

PC is a Dell Studio XPS 435T. Back-UPS ES 750 model BE750G serial #5B1114T22081. PowerChute Personal Edition 3.0 is installed and appears to run properly. It reports the load on the UPS is about 115W.

[BillP · Accepted solution]

Good day Bob,

Based from your description, it appears that the UPS that you got is incompatible with your Dell XPS system. The power supply on your Dell system is too sensitive with the kind of waveform that our BackUPS produce. Due to this waveform, although it produce ~115V AC the PC power supply doesn't detect an input power.

Here is a link that explains other reasons why would a load reboot or turn off when BackUPS runs on battery: [Equipment connected to a Back-UPS product turns off unexpectedly and/or reboots.|http://nam-en.apc.com/app/answers/detail/a_id/20/kw/equipment%20reboots] Check out problems 5 and 6.