The service is required to have a grounded conductor run. After that point though, if all my loads are line to line, what is the purpose to have a grounded conductor to a sub panel?You are saying 3 wire sub panels are compliant?
I am asking. Why would anyone set a sub panel with a 3 wire feeder?
I know it would be a four wire feeder if I was installing it.
Even with a 120 volt service, you still have the grounded conductor.