Years ago during a week-long power outage, a telephone central office where we had some equipment suffered a generator failure. The telephone company had a backup plan (they kept one generator on a trailer in the city for such a contingency,) and they had battery capacity[0] for their critical equipment to last until the generator was hooked up.
They did have to load shed, though: they just turned off the AC inverters. They figured anything critical in a central office was on DC power, and if you had something on AC, you were just going to have to wait until the backup-backup generator was installed.
0 - at the time, at least, CO battery backup was usually sized for 24 hours of runtime.
> had some equipment suffered a generator failure. The telephone company had a backup plan (they kept one generator on a trailer in the city for such a contingency
Well that’s more forward thinking than AT&T’s Nashville CO when it got bombed. They just depended on natgas grid for their generators if grid electric went out. They underestimated the correlation between energy grids.
When natgas got cutoff and the UPSs died, they had no ability to hook in roll-up generators and had to hastily install connection points (or hardline them). And no standby contracts for them.
To be fair, the CO I described[0] is a local switching center. The Nashville “CO” was the area long lines/tandem/long distance site. Now, I’m not defending the lack of a backup plan, but tandems tend to be far larger than a typical local/class 5 CO.
0 - which like the Nashville long lines building also happens to be a pre-divestiture AT&T site, although at the time it was owned by BellSouth. It is also in Tennessee, although in Memphis, not Nashville.
They did have to load shed, though: they just turned off the AC inverters. They figured anything critical in a central office was on DC power, and if you had something on AC, you were just going to have to wait until the backup-backup generator was installed.
0 - at the time, at least, CO battery backup was usually sized for 24 hours of runtime.