I ran a Swan Mark-III (2x3-400z) PS on 120vac in a bedroom (My ham shack) running 2500vdc @ 400mA (1000VA) to run my 2m-8877 to 600w output. That PS drew at least as much as the KPA500 will. I only saw a slight momentary flicker in the room lights when I switched to transmit (I am transmitting key-down for one minute using digital modes).
I only ran 240vac when I upgraded to a 4kV@1amp HVPS. I ran 35-foot of #8-4 wiring to a small breaker box with one 20A 240v breaker and two 20A 120v breakers. That provided some separate circuits for my low-voltage PS so that the rest of the ham shack could run on the house circuits. Now I am adding a 3500VA 50vdc PS for 6m-QRO, so will have to add another 240v outlet. I will not add any breakers since I will not run both 6m-QRO and 2m-QRO at the same time. The HP switching PS (50v@50A) only cost me $18 on e-bay! It will supply a Harris Platinum 1100w SSPA (16 LDMOS transistors) that is a pull from a chan-2 TV station. They were used as drivers for 50kW transmitters! ---------------------------------------------------------------------- Message: 1 Date: Tue, 03 May 2011 19:32:33 -0700 From: Jim Brown <j...@audiosystemsgroup.com> Subject: Re: [Elecraft] [KPA500]KPA500 power cord question To: elecraft@mailman.qth.net Message-ID: <4dc0bac1.60...@audiosystemsgroup.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed On 5/3/2011 11:20 AM, iain macdonnell - N6ML wrote: > I'd be interested to hear about benefits (if any) of running the > KPA-500 on 220V vs 110V (in the US) The only good reason I can think of is if the 120V circuit that runs your ham shack would be overloaded by adding the amp. That's a rather unlikely scenario. A single 15A circuit is good for 1,800 watts. The KPA500 specs say it needs 1,000 VA, which is 8.3A. That leaves 6.7A (800W) to run the rest of your ham gear. Because most power amps, including the KPA500, get to full power with less than 50 watts, you'll only need about 2A at 120V for the transceiver. Even with SO2R, you're only transmitting with one radio at a time, and transceivers don't burn my power in RX mode (especially Elecraft radios). The one good reason for having 240V in your shack if if you think you might want to run an amp rated at 1kW or higher, or if you might need a space heater. If I were pulling new wiring into a ham shack, I would install one 20A 120V circuit and one 20A 240V circuit for ham gear (and computer gear) only. I would put LOTS of outlets on the 120V circuit, and I would put them in steel backboxes that are all bonded together, and to the backbox for the 240V outlet. If I thought the station might someday want to do multi-two contesting, I would double up both circuits, but I would still keep them all bonded together. 73, Jim K9YC 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com EME: 50-1.1kW?, 144-1.4kw, 432-100w, 1296-testing*, 3400-? DUBUS Magazine USA Rep dubus...@hotmail.com ====================================== ______________________________________________________________ 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
