>Rich says;
>
> >... length helps because it lower the V gradient. Two 10w resistors in
>
> >series are better than one 25w resistor.
>
>Very true - I use one resistor in the present PSU, but it's about 6 inches
long
>and 1-1/2 inch diameter, though. (Over the years, I've collected
>physically big
>vitreous enamelled resistors of 50 watts and up in various values) An
>important
>point is the pulse rating, as there's a lot of energy to dissipate. For
>instance, a 5 watt resistor 6 inches long may well not flash over because of
>voltage gradient, but explode with the amount of energy involved.
? When a resistor explodes, there is a flash over.
>
.........
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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