[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: MOT help



Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Kidd6488-at-aol-dot-com>

OK, 
There is one main difference between OBITs & NSTs and Pigs, PTs and MOTs
(besides the power) The first are what we call "current limited." This means
that they can limit how much power they put out all by themselves. Just plug
'em in and go.  But MOTS (and the others) are not. So if you plug them straight
into the wall, they will keep drawing more and more amps indefinitely until the
breaker kicks out. To keep this from happening, we must "ballast them." Many
things can be used as ballasts: 

hot water heater elements 
stove elements 
dryer elements   ??? 
arc welders 
other MOTs 
a specially wired VARIAC 
even a light bulb (i think) 

You simply hook your ballast up in SERIES with the mains going to your
transformer. This keeps it from drawing too many amps. It is sometimes helpful
to build a special extension cord with a box on one end with a standard outlet,
only when you wire it up, break the little tabs that connect the two outlets
and wire them in series (instead of parallel like you normally would). So the
incoming 'hot' would go to the 'hot' side of the first outlet, a jumper
connecting the 'neutral' of the first outlet to the 'hot' of the second, then
the incoming neutral to the neutral of the 2nd outlet. The third wire ground
then goes to its normal screw. This then lets you just plug your trannie and
ballast into either of the plugs on your cord. 

Now someone correct me if I'm wrong, but in order to see how many amps you are
actually supplying your transformer with, you just see how many amps it (the
ballast) would normally draw. I don't know for sure about non-current limited
ballast, like another MOT, but I would guess somewhere around 10-12 A. 

 From what I have heard, MOTs hardly EVER work with a Jacob's Ladder. You can
try hooking 2, 3 or 4 MOTS together (any more and the insulation would probably
fail) and then do the Jacob's Ladder... Quite a spark I would imagine! 

If you only have one MOT and don't plan on getting any more soon, there are
other things you can do with them: 

Make a spot welder (check the archives  [Terry, the link?]) 
make a current sensing transformer (again) 
or anything else needing a heavy duty primary... 

Have fun, and stay safe... 

--------------------------------------- 
Jonathon Reinhart 
hot-streamer-dot-com/jonathon