APC Back-UPS ES 700 reboots my computer!

[Anonymous user]

Dear people on this forum,

I have an APC Backup-UPS ES 700 plugged in the UPS port of my iMac. I manage it through directly through the OS, I have MacOSX 10.7.2.
It has worked fine without any problem since I bought it, last august.

Since yesterday, without any apparent reason, it reboots my iMac. I tried to change USB port, but no way... after 5-10 minuts after rebooting my computer, it reboots it again!
The battery is fully charged, according to the bar showing in the energy saver control panel. there were no blackouts or other power cuts.

If I leave the iMac power cord plugged in the UPS, but not the USB cable, it works... no reboots. It has been this way for many hours, today.
As soon as I plug in the USB cable, within few minutes (5-10 at max), it reboots my mac.
Definitely, there is a problem with the auto-restart feature. I did not install any new OS upgrade or software dealing with power recently... and as I said, it worked fine so far.
I tried to turn it on/off, the iMac power cord is plugged in the battery row, the master is not enabled...

Does anybody has any suggestion for starting troubleshooting this problem? I am already out of options...
thanks!

[Anonymous user · Accepted solution]

Sorry... I meant power cord plugged in the UPS, and the UPS USB cable plugged in my iMac. It looks like few words were skipped...