Re: 365 Main reason for outage report published

Register4Less recently reported a power failure in Montreal where the return of a single cycle from the utility tricked generators into shutting down all three cycles, throwing the data center onto UPS until the batteries died. They did not report make of generator or of the board that failed them.

Many generator control systems (and transfer switches) do not monitor all three phases for voltage, and stability (phase sync). Any of these can cause a UPS to use its batteries (without charging) and not fire up the generator. Or conversely, allow a generator to power down. Its happened to lots of people in various places, but I am not going to name-names. DJ