Building ATS with contactors

Thread Starter


Joined Jan 8, 2015
Dear all,
In other thread I have posted about wiring motorized change over switch. That project failed so I decided to build my own ATS. But I want to be clear the safety issues associated.
To be specific I put my questions as follows.

1. I have read that there should be both mechanical and electrical interlock between main and gen contactor. But can you see any mechanical interlock in the pictures of a commercial ATS attached here.
2. Can I build my own ATS by using two contactors and interlocking them by using their auxiliary contacts only?