alan smith wrote:

> I agree with Mike...its not to code, and I am still discussing with the
> client on what he wants.  He is going to do some measurements on the
> current draw for me, and from what he has stated the normal draw is
> around 8A so thats within 16AWG wire.  However the concern is also the
> stall current that he said was around 25A but is going to confirm for
> me.  If it spikes at 25A, and I shut it down after a second or two
> (using a current sensor) the wire should still be OK then.  I was
> planning on using THHN, and it will be 'open' to the extent that it will
> be 4 wires in an open bundle. 

For such thermal pulse responses, you can think of the system as a current
source (current = thermal power), connected to a series of RC low passes (R
= thermal resistance, C = thermal capacity), terminated by a final R to
ground (thermal resistance to ambient temperature). The voltages at the
nodes correspond to their temperatures.

Usually the "termination resistor" is the most difficult part -- which
somewhat limits the usefulness of this analogy, as it is usually also the
most determining part for the various temperatures.

Gerhard

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