Can you tell me how to get my Back-UPS ES 550 to stop its screech? It is a model # BE550R. I suspect there was a power outage. The "Replace battery" light is not on so I assume it is fine.  I have a simple paper shredder plugged into the surge protector and it works, but I am afraid to plug my computer in, in case it has some electronic problem. I have tried unplugging the unit and also hitting the Reset button, but still a shrill continuous sound. 

Hi,

Try the reset procedure and after that if the unit still makes the noise it should be replaced.

1: Disconnect any attached load.

2: Unplug the UPS from the wall socket.

3: Disconnect the UPS' internal battery.

4: Push and hold the "On" button on the UPS for 5 seconds

5: Reconnect internal battery.

6: Plug UPS in to known good power source.

7: Turn UPS on.

Thank you, but how do i disconnect the battery? I got it out, but there is a black wire & a red wire. Which do I disconnect & how?

Barbara Hettwer

Hi Barbara

This video shows you how to disconnect and reconnect the battery

https://youtu.be/_dydlRHFjrc

Regards

Matt