That is correct as far as changing between 115 and 220VAC mains goes, but there's a little more to it than that. The power supply is not regulated, so its output can vary depending upon the actual mains voltage supplied within the nominal 115 or 230VAC ranges.
Secondary taps on the power transformer allow you to compensate for normal variations in mains input voltages to produce the correct d-c output voltage from the supply. The output voltage should be checked and the taps adjusted as necessary any time you move the amp to a new mains outlet (or, of course, if you switch from a 115 to a 230 VAC mains supply). This is all described under "Mains Voltage Settings" in the Installation section of the manual on pgs 6 and 7 in the Rev B manual. It's immediately after the information on installing the fuses and the fuse holder. The procedure involves only removing the top cover and attaching the tap wire to the rectifier board that produces a voltage in the proper range as indicated on the KPA500's LCD. The wires use spade connectors that require no tools to connect. Ron AC7AC -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Doug Person Sent: Saturday, July 09, 2011 10:46 AM To: [email protected] Subject: Re: [Elecraft] Operating KPA500 on 220V I meant to say change the fuses and reconfigure the fuse block... I was actually reading the manual when I asked that question. On other amplifiers I was required to change internal transformer wiring to setup for 220v. That's what I meant to ask. So switching the fuses and changing the fuse block is all I need to do. No other internal wiring required. Doug -- K0DXV On 7/9/2011 9:43 AM, Ron D'Eau Claire wrote: > When you change the fuses, you insert the fuse holder so 220 is visible in a > little window instead of 115. That changes the wiring to the power > transformer input for 220 volt mains operation. It's described at the > beginning of the Owner's manual. > > Ron AC7AC > > -----Original Message----- > Am I correct in assuming that in order to run the KPA-500 on 220 volts > all that is needed is to change the fuses to the provided 6 amps, wire > the correct plug on the power cord and the power supply will adjust > accordingly? > > Thanks, > > Doug K0DXV > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] 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:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
