This reminded me of James Hamilton's (the AWS datacentre guru) writeup of the power outage at the 2013 SuperBowl. Specifically how the default configuration of backup generators is often to protect themselves, even if that means shutting down the things they are meant to keep running. In my own experience running a reasonably sized datacentre I was often surprised at how UPSs and generators reacted to adverse conditions. One thing with power that you don't want is to be surprised. But it's difficult to test this equipment so it's mostly a learn as you go experience.
https://perspectives.mvdirona.com/2013/02/the-power-failure-...