Tom wrote: one thing I think which may have been missed, or at least glossed over, is the fact the Astron supplies include a very good FOLDBACK CURRENT LIMITING circuit which, if directly shorted (e.g. HOT lead directly to GND) will instantly reduce the output current (and the voltage) to nearly zero with little or no damage to the supply, the attached equipment, OR to the cabling (or user).
--------------------------------------------------- Quite true, Tom. And that's why I said one must be careful with a high-current supply. It's a lot harder to trip that crowbar circuit on a big supply! As I pointed out, a 13.8 volt, 50 amp supply will deliver full current into a 0.3 ohm load WITHOUT OVERLOADING! That's 690 watts that can cause a lot of heat in short order, and it won't even trip the crowbar. Where I've found some ops get a nasty surprise is that they've become used to seeing the crowbar kill the output when they accidentally short out a 5 or 10 amp supply, but when they do that with a bit of solder or wire on a 50 amp circuit, they're met with a face full of molten copper, solder or whatever it was that got across the circuit and the power supply barely hums... Ron AC7AC _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
