yep - if you tested earth or neutral to 1,2,3 you could get a backfeed thru the windings to simulate 240v present when it itsnt- if that makes sense, always best to change contactor/overload when changing a pot- ac2000 did an 8 cylinder trane pot once- crane job at hmv mcr- i went 2 days later an pot knackered as they didnt change the contactors- still had the silver stickers trane id the electrics!- oops