On Wednesday, October 13, 1999 12:05 PM, measures
[SMTP:measures@vcnet.com] wrote:
> >
> >On Wednesday, October 13, 1999 10:20 AM, measures
> >[SMTP:measures@vcnet.com] wrote:
> >> >
> >> >Hello all...have an old alpha 374 the resister across the step
down
> >> >relay, a 10 ohm 13 watt wire would burned up....question...can I
> >replace
> >> >this with a 10 ohm 20 watt, what I have available or should I
replace
> >it
> >> >with an exact same wattage??? thanks all Tim WB8OWX
> >> >
> >> I have seen ww resistors of the same physical size rated from 10w
to13w.
> >
> >Your point?
>
> The ratings game is just that. 13w rated and 10w rated vitreous
coated
> ww resistors are 2 inches long and 0.4 inches in diameter.
> >
> >> A 10w, 10-ohm resistor should probably work ok in this
application.
> >
It sure gets crowded on a head of a pin.
He has a 20W unit, apparently in hand. Why would you feel it necessary
to tell him a 10W would work and not answer his specific question and
tell him if a 20W is OK?
>
> >
> >> However, there is a chance that the resistor was not defective in
the
> >> first place, and there is a circuit fault which caused the failure.
> >>
> >
> >True enough, but since a 10W "should probably" maybe it "might not".
>
> My guess is that a 7-watt rated unit would work in this (intermittent)
> application.
>
Maybe even smaller. In this application it probably depends more on its
construction than its power rating per se. I agree the real problem is
why it "broke" in the first place. If being underrated caused the
problem then bigger will be better. If not, then it won't help much -
just cook longer probably.
I'd treat it much like a blown fuse: replace it once and see what
happens - if it blows again, troubleshoot. Unlike a fuse, it probably
won't "blow" right away even if there's trouble. So there'll be time to
see (smell?!) if the rest of the circuit is operating properly.
Ciao
Mike
N2MG
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