Ignoramus19762 fired this volley in
:


Brian Lawson is correct for a series circuit.


No, Ig. The point of highest power dissipation will be. Sorry, but he's
dead (old wive's tale) wrong.

If you had a "short circuit" with a resistance across the short of 10
ohms, and 220V across it, what would you get? (ok... rhetorical..) you'd
get a current of 22amps. 22 amps across 10 ohms would be 4840 watts.
That's a fair bit of heat.

Now "conduct" the same experiment with 10 gigaohms.

Tell me how much heat you generate, and whether or not it's discernable
against the background.

In _any_ given circuit, the "highest heat" will be generated in the
highest resistance portion of the circuit, but it's a fool's exercise if
no measurable current flows. The friggin' guilds are teaching these guys
that 10 million megohms of resistance constitutes a "high heat" short in
a 220V line. They don't even _know_ what the term "insulation
resistance" means.

I've had more than one "trained electrician" give me that crap.

I also watched one blow off two fingers with a "lowest resistance" short
in a 440 3-ph panel.

In the end, power supply circuits are limited in current, but you don't
know, can't tell, and will never be informed of what the resistance of
the circuit is. It might not even be limited by resistance. It could be
an inductive reactance issue.

Keep the idea "maximum power" at max(I2R). It's not the greatest R, it's
the greatest product of I2 * R.

LLoyd


LLoyd