Good Evening. I am working on a 9 year old 5kVA Multiplus. It has been running for 9 years off grid so constantly inverting from day one. The right hand transformer is making a load vibrating/resonating loud noise even with moderated loads. Right hand transformer silent on bench test with AC input. It seems like the right hand unit has started to get tired. Can we swap the two units so the left hand unit now takes over the work from the right hand unit?
