Why would my UPS cycle on/off at about the same time each night?

[RKP5637]

12. I'm wondering if someplace there is some heavy load placed on the lines around 1AM? This is a

residential area here, but maybe there is a heavy load on the lines around 1AM? Also, they have been doing major upgrades to the power lines. Maybe there is some night crew activity someplace around 1AM? No idea.

Last time it did some weird things an underground feeder line blew up and the crews came out and replaced the lines, but that time the UPS went randomly into backup for a few seconds at a time. I was going to replace the batteries, but there is absolutely nothing to indicate it has bad batteries. It passes self test OK and if unplugged it goes into backup and supports the system with no problem at all, and the battery indicator lights stay on/stable. I think what I'll do is wait and see if it clears, eventually.

I'll post back in awhile and let you know what's happening! Thanks for your posts, really appreciate it!