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Re: Ok.. where am I going wrong



Replying to my own reply
Big oops.
Michael,
Please disregard my first post. I wasn't thinking "AT ALL"!  I'm definitely
not a
morning person. Completely missed what it was you were doing. Yes, if you
measured
a voltage drop of 17vac across the 0.4ohm resistor, you should have 42.5A
flowing
through the resistor. The remaining voltage drops will total your applied
voltage.
Since your 30A fuse is not blowing under a sustained voltage, do you
possibly have
the ballast in parallel with the resistor? This of course would change the
R value
as R||XL must be accounted for.
Sorry about the first post. I'm sure to get blasted on that one (well
deserved).
Bart

Tesla List wrote:

> Original Poster: "Barton B. Anderson" <mopar-at-uswest-dot-net>
>
> Michael,
> For current flow, you must have both sides of the AC joined together. The
> current flows back and forth from one leg to the other through the
> components in
> your circuit. The components are all in series forming a circuit "loop". The
> 0.4ohm resistor is just one component in the loop. In order to "calculate"
> current flow in the total loop, you must account for all resistance
including
> the resistance and reactance of the ballast, pig, etc... If your 0.4 ohm
> resistor was the only thing in the circuit, then you would draw 40+ amps
> across
> the resistor and blow your fuses. Obviously, the current is being limited
> by the
> other components in the circuit.
>
> Hope this helps,
> Bart
>
> Tesla List wrote:
>
> > Original Poster: "Coiler" <mycroft-at-access1-dot-net>
> >
> > I just finished wiring up my pig-training facility. This means the
> > welder, 0.4 ohm resistor and 240V feed. I had thought to calibrate the
> > switch settings on the welder to KVA numbers by taking voltage readings
> > across the resistor. The infamous V=IR business. Only.. it didn't work.
> > Or I don't think it did. At one point, I measured a drop of 17V. This
works
> > out to roughly 42 amps. This cannot be. I have 30A fast blow fuses in the
> > line
> > and I suspect that they would fry in short order at almost 50% overload.
> > Therefor, there must be someting I am missing. I assume it is related
to the
> > fact that this is AC.
> > Could someone help me out here? Tell me where I goofed.
> >
> > Michael Baumann
> > Coiler, Homebrewer, Nerd. mycroft-at-access1-dot-net