Phil, the 20 VAC drop that you describe for a 15 amp draw on a 120 VAC circuit strongly suggests that something is wrong with the wiring.
I am assuming that with a 15 amp breaker the circuit is wired (per the National Electrical Code requirements) with 14 gauge copper wire. A voltage drop of 20 VAC, or 16.3%, would be consistent with a wire run of 250 feet. Even running along the two legs of a triangle (not the more direct hypotenuse), your wire run is probably no more than 60 or so feet, unless you own a very large house. The voltage drop should be 3 or 4 volts at 15 amps, not 20 volts. Either there's a connection in the circuit that is creating some resistance, or the wiring is undersized (unlikely). If you have an oxidized or otherwise "non-clean" connection (such as a wire that has been arcing under the connecting screw or a loose connection inside a wire nut) you have a real fire hazard. I suggest a careful inspection of every joint in the wire run from the breaker to the outlet. If you don't see anything obvious that you can correct, call an electrician. House wiring is quite different (mechanically, not electrically) from the sort of wiring we're accustomed to dealing with inside a radio chassis. Unless you know for sure what you're doing, and know the NEC requirements, this is a job best left to professionals. Lew K6LMP On Feb 16, 2011, at 9:36 AM, Phil & Debbie Salas wrote: > I ran 240VAC to my shack for my ALS-600. I have the switching power supply, > and the ALS-600 draws very close to 15 amps with the switcher. As my shack > is diagonally across the house from the breaker panel, I was actually seeing > 20VAC drop in the wiring. This caused two problems: Lots of light > flickering in the shack, and sometimes the power supply would trip out > because as the input AC dropped, the input AC current would increase and trip > the ALS-600 switching supply input current sensor. > > However, the KPA500 only draws about 9-amps at 120VAC. While I could set it > up for 240VAC (and I probably will one of these days), at 9-amps there is no > lamp flickering in my shack, no noticable AC voltage drop, and I can put out > the full 500 watts with no problem. > > Phil - AD5X > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
