DB> Well this thread is getting kinda strung out, but have any of
DB> you guys considered using something other than a diode on PV
DB> panels?
DB>  seems like I could use a 20 amp relay powered by a paralel tap
DB> on the panel that would only draw (thru a 200 ohm coil) 60ma
DB> or less than one watt, and diddly for heat.
DB>  Or maybe one of these new IGBT gizmos, that says it has .05
DB> volt across it, and diddly for the drive on the gate.
 Why not use a MOSFET ?
 How are you going to determine the time to switch ON or OFF?
Normally, that would be done by sensing a voltage drop.
 This is why I suggested a Schottky diode. IR has one that's
rated at 9 Amps and .25 VF. They also have one that's
rated at 19 Amps and .32 VF.
 Yes, they waste power; but, not THAT much (IMO) and they're
simple and reliable.
 TTYL.
 Robert
 * SLMR 2.1a * Clinton: Taxation without hesitation.
--- Platinum Xpress/Win/Wildcat5! v2.0
---------------