Important takeaway from https://www.northamericaphaseconverters.com/resources-assistance/rotary-phase-converter-faq: "a rotary phase converter must start first before a load is applied." So we've been very lucky and/or the GWM is very robust.
Caps were recently replaced not necessarily because...
Good point, and there is no zero-crossing in 3-phase power to eliminate the transients. I was told what you suggest trying (close the second switch before starting the converter spinning with the first switch) could cause damage. I never questioned that advice; maybe I should have.
We destroyed* the 3-phase pump motor for our neighborhood swimming pool and wonder if the startup procedure we've been using for at least a decade needs improvement.
Property has only single phase 240V service so we have a mechanical phase converter to provide 3-phase power to pump motor...
