I have two Prewar Lionel 91 circuit breakers. One has two terminals A and B. The other has three A, Low and High. Can anybody tell me at what level these should trip? Are they reliable enough to protect the transformer?
Any help is greatly appreciated
They can protect a pre-war transformer they were made for. You can load test a short to see where they trip. I would guess no two are the same.
I would not trust them on newer stuff. To many better options out there.