Don makes very good points here. Our hour built in 1979 is wired with
#12 for all outlets and lights. HOWEVER, the outlets and switches all
used the"backstab" connections. In my efforts to resolve an issue, I
found that several showed signs of heating. Therefore, I replaced every
outlet and switch. I used the "hook the wire around the screw" method
and made sure everything was tight.
After doing so, I noticed my occasional light flicker was no longer
present and my noise on the receiver was reduced. Radio wise, I ran a
dedicated service, 240V, from the breaker panel to the operating
position and a dedicated 120V service for a pair of duplex receptacles.
I strongly suggest you check yours or have a qualified and licensed
electrician do so. It just might save your house from an electrical fire.
Radio wise, you can have the confidence you have a solid dedicated
service for your equipment. By running almost any power amp from 240V,
the line IR drop will be minimized, voltage regulation will be improved
and IMD will be reduced as the result of your efforts.
73
Bob, K4TAX
On 10/29/2017 10:43 PM, Don Wilhelm wrote:
Robert,
The KPA500 will run OK on 110 (actually 115 or 120) volts.
The real question is how many other receptacles are on the same 120
volt circuit. Are there any other large current drawing loads on that
same circuit, and how much wire run from the breaker box to the
receptacle being used.
Figuring an efficiency rating of 50% for the KPA500, the current draw
for the KPA500 will be 9 or 10 amps. The common receptacles are rated
for 15 amps, and it depends on whether the wire size used is #14
(usual) or #12. The smaller wire will have more voltage drop.
Electrical code requires #12 wire for kitchen outlets in modern
buildings. But the remainder can be #14.
The other thing is that if the receptacles were wired using the
"backstab" connections, that can create a higher resistance. I would
have an electrician check all receptacles on the circuit feeding the
receptacle and change any receptacles using the 'backstab' connections
to the lower resistance wires placed under the receptacle screws.
Since I had the advantage to wire my own house, I used #12 for all
receptacles, and in the hamshack area, I have a dedicated circuit for
the two receptacles there. Most installations cannot boast of that
same advantage.
73,
Don W3FPR
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