[Elecraft] KPA500 AC power

[James Bennett]

Jack - great answer, many thanks for clearing it up for me. Our home was built in ‘91 so I would guess that it is fairly up to current code, wire-wise. Guess I’ll save my $600 for something else. Maybe a trip to the casinos in Tahoe! Or paying some bills. Hmmmmm... :-)

Jim Bennett / W6JHB
Folsom, CA

> On Dec 12, 2018, at 4:44 PM, Jack Brindle <jackbrindle at me.com> wrote:
> 
> James;
> 
> There would be no difference in the heat generated inside the KPA500 since the KPA’s transformer is delivering the same voltage and current in either case. The entire difference would be voltage drop on the power line and KPA’s power cord due to the higher current at 110V. The losses are I*I*R, where I is the current and R the power line resistance. Noting that the current is double for 110V, the heat losses in the power line will actually be quadrupled.
> 
> If you have #12 wire in your walls (the current NEC code), and use the supplied power cord, things should be just fine.
> 
> 73!
> Jack, W6FB
> 
>> On Dec 12, 2018, at 4:27 PM, James Bennett via Elecraft <elecraft at mailman.qth.net> wrote:
>> 
>> I’ve wondered the same thing here. While I don’t have the flashing lights that Dennis  NJ6G does, I DO have a ton of other things plugged in to outlets in this room.
>> 
>> Am I off in left field on this: if the amp were to run on a 220 circuit it would obviously draw half the current, and thus (to my uneducated brain) less current “might” mean less heat generated and a lower temperature inside the unit. Does that make sense? 
>> 
>> I had an estimate from a licensed electrician who said it would run me about $600 to put a 220 outlet in the shack, due to it’s distance (and obstacles in the way) from the electrical entry panel.
>> 
>> Kinda pricy, but eliminating some heat in the shack and keeping the KPA500 fans running slower would be nice….
>> 
>> Jim / W6JHB
>> 
>>> On Dec 12, 2018, at 4:13 PM, Tom Berry <tberry1 at triad.rr.com> wrote:
>>> 
>>> Is there any advantage to use 220 V over 110 V on the KPA500?
>>> 
>>> Is it worth having an electrician come to the house and install a 220 V outlet for it?
>>> 
>>> 
>>> Thanks
>>> 
>>> Tom AA4VV
>>> 
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