REFLECTOR:A (re)volting problem

Dave Black reflector@tvbf.org
Fri, 03 Oct 2003 18:09:04 -0400


Chuck,

> Well said, even if I'm not sure I could repeat it, but I get the general
> drift and concept.  

I'm not sure I could either...

> In short, the popping 10a breaker is an likely an indication of a short, 
> since, by your calculation (and explanation) a 5a breaker should be 
> adequate, and certainly a 10a breaker may actually be oversized.  

Yes. A 10a breaker should be more than adequate. The main thing the breaker
protects is the wiring, and in this case anything up to a 15a breaker would do
that. 

> I'm going to do some electrical checks this evening, looking for
> a short, partial short as well as a direct measurement of amp draw if I
> don't find anything on the short-hunt.  I can always dream that it's just a
> weak breaker.

It's possible. The quickest way to tell is to measure resistance across the
pitot tube. You should get something in the vicinity of 4 Ohms, since this is
a 24v tube. If it measures less than 1 Ohm, you probably have a short inside
the tube. If I recall that this tube went through a plating process
unprotected, that's most likely when the short happened. 

> The way the wind feels this evening, I may need to start using the pitot
> sooner than I thought!

Same here!

Dave Black
Shortwing RG