Startup during power failure.

[Anonymous user]

I have an APC900xl that I usually have powered off. I don't really use it for protecting equipment from power failure. I only use it after a power failure when and if I am home, else I don't need it. Unfortunately, it doesn't start unless it has AC power first. Consequently, if the power has failed it can't be subsequently started It just seems dead, no lights, nothing. The batteries are fully charged.

After power comes back on no problem, it starts and will provide backup if power subsequently fails. Again, I don't want to have it on all the time, I just want to use it after a power failure.

I would think some option exists to allow a "no AC power" start-up, but I can't find one.

This irritating behavior also prevents me from shutting down and re-starting the next day. During Sandy I wanted to run my equipment for a short time every day, but this was not possible without having AC power.

Any suggestions on how to cope with this problem?

I have seen other UPS' with the same irritating behavior. Any idea why they are designed this way?

[BillP]

it sounds like you need to try the "coldstart" procedure which allows you to start the UPS with no AC input. to do this, you would disconnect from AC power and then hold down the power button on the UPS. with most models, there are two beeps and you are to let go of the power button during the second beep. if you plug the UPS into good AC power while in this mode, it should come online. if no AC is present, then it will just run off of the battery.

this is not the intended operation of a UPS normally so that is why i don't think it is stated out there in the open. the UPS is designed to run online most of the time and toggle between on battery and online as needed. most customers are not using the configuration you are so its not something that we advertise and recommend. you can certainly do it if you want and it won't cause a problem. we only generally use it to verify the UPS can start on its own (to test the battery, etc).

[Anonymous user]

I tried your cold start procedure and did not get any response. The UPS seems completely inactive, no lights, no sounds, etc without initial AC power as mentioned previously.

The APC manual for the 900xl makes no mention of the cold start procedure although I do see that in other manuals. I'm guessing the 900xl does not have this feature.

I wondering if I can kick start it with my modified sine wave inverter.

[BillP · Accepted solution]

well, what is the specific model off the back/bottom of the UPS on the white sticker with the serial number? i can verify that way. i guess i sort of assumed it was a newer model but i can double check once i know the exact model.