Back UPS ES 500

[dimm0k_apc]

This was originally posted on APC forums on 7/16/2009

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I have had the Back UPS ES 500 for a few years now and it's been running nice with an old Pentium 100MHz computer, DSL modem, wireless router, and network switch plugged in. That is until recently when about a month or so ago it started to emit a loud constant beep at night when everyone was sleeping. Not able to get my brain to fully recognize what was going on the easiest solution was to press the power button and turn off the UPS. Turning it back on killed the noise and so I left it at that. About two weeks ago it did the same thing and I repeated the power off/on cycle and again it was back to normal. This morning however it proceeded to emit the same tone, but turning it off and back on again didn't resolve the emitting of the constant beep. I've left it off for almost the whole day now and still get the constant beep when I turn it back on. I've tried turning it on with nothing plugged in, but no go. All the outlets work fine on the UPS despite this constant beeping. Anyone happen to know what's going on here?

[Techie_apc]

This was originally posted on APC forums on 7/17/2009

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Nelson,

Has the battery ever been replaced in this unit? Could you please provide me the exact model number of the UPS? You can find it on a white bar code sticker at the bottom of the UPS. The exact model number will help us to identify what is going on with the UPS. What is the light(color of the light and status of it- whether it is flashing or solid) indication on the UPS when it is beeping constantly?

[dimm0k_apc]

This was originally posted on APC forums on 7/17/2009

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No, the battery has never been replaced... never had any signs to do so. The exact model number listed on the aforementioned sticker is BE500U. I believe that's it and the characters underneath that is the serial number? There's a green light right next to the power button that's flashing while the unit is beeping. A steady flashing green light with no other lights anywhere else.

[Techie_apc · Accepted solution]

This was originally posted on APC forums on 7/17/2009

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Nelson,

The BE500U performs a self test to check the battery integrity every 14 days and at start up. If the unit fails the self test, it will make a constant beep with flashing Green light.

Please view the below K-base document which addresses your issue.
http://nam-en.apc.com/cgi-bin/nam_en.cfg/php/enduser/std_adp.php?p_faqid=16

So, it is the indication of the bad battery, and the battery needs to be replaced.

Yes, the Serial number of the UPS is located below the model number.

If you wish, you can trade in your unit to a new unit. Click on the below link to know more about trade UPS program.
http://nam-en.apc.com/cgi-bin/nam_en.cfg/php/enduser/std_adp.php?p_faqid=298

I hope that this helps.