@O Gauge Jim, I too service transformers, but do not have a 50% failure rate on the original circuit breakers in 1033's or similar. I'm interested in your test criteria if you'd share.
Note: This is not an argument against external breakers. Any transformer, classic or modern, should have external breakers and TVS diodes installed as appropriate for the application.
Good Morning BMoran, when testing the circuit breaker on a 1033 transformer, I put a dead short across the output terminals A and U using a #12 copper wire and slowly bring the voltage up and I like to see the circuit breaker open within five seconds, but seven max and normally prior to me getting to the full output voltage. Am I too conservative, maybe, but I had rather error on the side of safety. Somewhere in my archives I have something in regards to the amount of time Lionel specifications require, however based on my experience as a long time electrical engineer, involved in electric power such as motors, small and large transformers with some transformers having primary voltage as high as 15,000 V and the design and manufacture of high-voltage electrical distribution systems for electric utilities, I came up with my own circuit breaker testing procedure and guidelines.
As for a 1033, when I repair or rebuild I also add a diode to replace the rectifier disc and a new power cord. I have found a replacement internal circuit breaker that I think I can fit inside the case, however with the time to re-wire and buy the circuit breaker it makes the price for the smaller transformer prohibitive.
I purchased during last fall (10) 1033 transformers to upgrade and recondition to sell at our late winter and Springtime time train meets in upper New England. Of that (10), 4 had inoperable circuit breakers based on my specs.
Like you, I tell anybody who has any electronic equipment on their layout, if they are using any post war transformers usually KW’s or ZW’s they should include a fast break external circuit breaker and a TVS diode. I keep a few of each on hand.
I live in Wilton, NH 03086. Could you give me your location. The reason being, I sometimes get requests from people a great distance away to rebuild a KW or ZW transformer. In those cases the shipping both ways becomes almost prohibitive. What I do is keep a list of other forum members that repair transformer so I can recommend someone living closer to them were shipping would not be nearly as expensive.
Hopefully I’ve answered your questions. If not please get back to me. Now that I’ve accomplished this task, I’m on my way outside to dig out of a wet, 12 inch overnight snowstorm. Have a great day, Jim Lawson
