I am continuing to track down my low voltage problem under load. I would guess that my wiring is at least 100 feet that I can see easily. I will try to track it back to the distribution transformer.
When I plug in a 1500W (12.5A if resistive) toaster, my voltage drops by about 2.5V. What range of values can be expected for series impedance and transformer regulation for home power?
Bill
-- Ferme le Bush
That sounds like less voltage drop than I would expect in 100' of #12 copper at 12.5a. My calculator says it should drop 4.825v
I remember 5% drop to the farthest load. 3% at a service.
Don't have exact numbers for you, but the bolted short-circuit current from a typical pole pig can be several thousand amps. So if we assume 4000 amps, then the transformer and feeder impedance would be 240V/4000A = 0.06 ohm.
daestrom
The problem has been solved!
I was zeroing in on the problem. Indications were a bad neutral somewhere. I hired an electrician to trace the problem. With all my book learning, I figured out that hands on experience was more important than anything else.
It turned out that the neutral connection in the panel box was loose. The electrican tracked that down, stripped off some insulation and ran the neutral through two logs instead of one.
Bill
-- Ferme le Bush
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