That's the difference between "service voltage" and "utilization
voltage". You'll find, for instance, that there are 240V and 480V three
phase services, but you'll only be able to buy 230V or 460V three phase
motors. The difference is in the "allowance" for voltage drop in power
distribution from service entrance to point of use (2% for NEC)
Just ballparking here.. AWG14 copper (which is what most houses are wired
with) is 2.5 ohms/1000 ft. To get to 0.16 ohms, you only need 64 feet.
There's two conductors, so if you're more than 32 feet from the panel,
you've got 0.16 ohms in series (not even counting the resistance of the
connections, switches, circuit breakers, receptacle/plug combination along
the way).
Most three phase motors here are 208/240/480 Volts. Same with multi-tap
transformers for lighting. Locally, nobody uses 14/2 with ground,
everything is 12/2 with ground. It even hard to find 15 amp breakers for
use with 14/2.
As for the shack wiring, check the 220 or 240, or 230, whatever you choose
to call it, should be the same distance. Voltages should be indicitive.
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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