-> CH> Re: Diode in solar system..
->
-> -> If you find the concept of 0.7 being an emf unconvincing, then
-> put a
-> -> voltmeter across the diode while increasing/ decreasing the panel
-> -> output eg by shading it. You will see that the 0.7v does not
-> change.
->
-> CH> Yep!  Not disagreeing with that at all.  I have used series-conne
-> CH> diodes in a number of applications to get a fairly stable fixed
-> CH> voltage drop.  Works well.
->
-> CH> I think what we have is a terminology difference, not an "electri
-> CH> one.  To you, the drop across the diode is fine.  To me, it's
-> CH> something I'd like to find a better way to do.  Nothing mutually
-> CH> exclusive there!
->
-> That word of yours "drop" annoys me. It ain't a drop, it is an opposi
-> I baulk at the impression that the diode is wasting energy, as would
-> "ohmic" ie resistive device. Getting hot!
OK, then why *does* the diode heat up when current passes through it?
Whenever I've used a set of series diodes to "lower" the 12v source
in a vehicle to run a 6v load like a radio, the diodes heat up.
If there is .7 volts measured across an individual diode, and it's
carrying 5 amps, and it's heating up in the process then it looks
like a voltage drop to me!  That diode is acting like a variable
resistor.  Less current, higher effective resistance.  High current,
less resistance.  Crude voltage regulation results.
-c-
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