I went to a yard sale the other day. In a box was a transformer, 10v.
There was a bell that had a little vibrating clapper that worked off an
electromagnetic coil, with a little breaker set to cause it to repeat itself
at a rapid rate.
There was also a "ding dong" chime unit in there, which I didn't want. I
wanted the bell for my shop for people to ring for service.
I now realize that the transformer probably went to the chime, as it has
chime written on it. The transformer has black/white/green lines and comes
off 110v, then has two screws for leads to the ringer.
I hooked it up direct to 12 v. dc, and it worked vigorously. I don't think
the electromagnets would be used in an ac setup. The bell has one hot lead
to the electromagnets, which are two coils with one wire running through
both of them, and then a green ground screw to the base.
My question is: What is the best way to determine how much voltage the bell
is rated for. No writing on the bell. If I had some fancy power source
that had voltage ranges, I could do this by just setting it. Would a 9v.
square smoke detector type battery have enough amperage to be a conclusive
test? I guess I could look through the hundreds of little power suppliers I
have and find a 9v dc unit, and cannibalize it.
Just don't want to fry if in the meantime. So, trying to find a safe way to
determine just what it is. Plus, it cost me a buck, and I don't want to
blow that. It is vintage, looks like the sixties, and looks like it has
never been used.