2) Allowing transformer fields to collapse. Even in phase, without a
delayed transition ATS you can end up with a partially collapsed
transformer field with a new field being created at non-ground state.
This can cause a transient back wave that can snap circuit breakers.
Yep, this one happened to us a few times before we switched to a delayed
ATS, was a PITA to debug and resolve.
a transformer should be switched to the network when phase is at
highest/lowest point, not at zero.
zero: highist current
highest/lowest point: lowest current
because it's a coil.
Kind regards,
Ingo Flaschberger
