Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

This early motor-generator demonstrator was purchased at Cabin Fever several years ago.  It did not stay in my collection for long, due to the fact that my son saw it and decided that it needed to be on his shelf, rather than mine. 

Its purpose was to demonstrate its use as both a motor and a generator by changing the energized field and the position of the brushes on the commutator.  While it was in my possession, I could get it to run as a motor, but was never able to get it to operate as a generator.  Despite the fact that my son is an electrical engineer, we have still never been able to figure out how to get it to work as either an AC or DC generator, which it is evidently capable of either. I guess modern electrical engineering degrees don't include a course in early motors and generators! 

It is still quite a nice example of an early demonstration device.  Made of cast iron, it is quite heavy and a great display piece. 

Beautiful motor Doug. I notice it has multiple commutators and looks like the brushes can be moved around--what does that achieve?

What a great historical piece you have there Doug.
As it does not have permenant magnets and the crank is not geared the output as a generator will be tiny.
It was probably used with a galvanometer wired to show output as well as direction change.

I wish I had an early galvanometer! It did actually read about .2 volts on my meter, so maybe it is working, just not what I was expecting. Thanks,
Doug