Re: Will I kill my MOTs?

["Tesla list" <tesla-at-pupman-dot-com>]

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

In a message dated 5/19/01 5:14:16 PM Eastern Daylight Time, tesla-at-pupman-dot-com 
writes:

> Hi list! 
>  I decided to upgrade my coil a bit, and first thing was the power supply.  
I 
> 
>  intend to use two MOTs back-to-back with center grounded.  I rigged them 
up 
>  with a 16A breaker (at 240v) and it made a nice little spark - I 
accidently 
>  knocked one of the wires and it sprang back, drawing the arc to over a 
foot -
>  
>  that scared me!  Anywayz, I am running them with no ballast.  They don't 
> trip 
>  the breaker but am I going to kill them over time by running them like 
this? 
>   
>  I have another, smaller, MOT that I could use as ballast but presumably 
this 
> 
>  would reduce the power somewhat.  Just wondering whether it's absolutely 
>  necessary to use it. 
>  Thanks 
>  Henry Hallam

Henry,

It's a matter of heat build up.  If the MOT's get too hot the insulation
can burn up, and the MOT will be destroyed.  Generally, they can
withstand a lot of heat.  I've run mine so hot, you'd burn your hand
if you touched the core (power off), yet the wire did not discolour.  
Discolouration of the wire is a good indication of too much heat
over time.  Smelling or smoking, is another strong indicator    :)

John Freau