26 Jun
2011
26 Jun
'11
5:43 p.m.
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