voltage drop calculations
#1
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voltage drop calculations
I had power dropped on my property and it is 350' to our build site. I want 200amp service at the house. what is my voltage drop going to be for the long run to the house, and what are the potential hazards for such drop? I had planned on running aluminum 4/0 4/0 2/0. I found an online calculator that indicated my voltage drop would be 2.86% based on 240v, AC single phase, single set of conductors at a load current of 200 amps. Do I need to worry about this? Should I have the power company move my meter base next to the house?
#2
The 2.86% voltage drop at 200 amps is not a problem.
Your choice, probably depending on cost. You would have to pay for the line from the present proposed meter location over to the new meter base at your house plus a separate pole transformer nearby. This line would be a medium tension (primary) line to eliminate the voltage drop problem.
Otherwise the long fat 120/240 volt line you first suggested has no greater hazard compared with a shorter skinnier line carrying the same voltage in the same manner (underground; overhead). If there is a whole house disconnect switch or breaker out at the meter base then you need a fourth conductor for ground running to the house panel regardless of distance.
Your choice, probably depending on cost. You would have to pay for the line from the present proposed meter location over to the new meter base at your house plus a separate pole transformer nearby. This line would be a medium tension (primary) line to eliminate the voltage drop problem.
Otherwise the long fat 120/240 volt line you first suggested has no greater hazard compared with a shorter skinnier line carrying the same voltage in the same manner (underground; overhead). If there is a whole house disconnect switch or breaker out at the meter base then you need a fourth conductor for ground running to the house panel regardless of distance.
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Thanks. I am assuming I had all my factors correct that I plugged into the online calculator, and if so i take it the 6.86v drop is nothing to worry about. I forgot to mention I would pull a ground wire as well.
#4
Your load will not be 200 amps, that is the max rating of the breaker. You need to do a load calculation to determine the load that will be on the feeder. Voltage drop is calculated by voltage, current, distance, and wire material.
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Thank you, based on a formula I found online my load current came out to about 120 amps. that puts my voltage drop at 2.7%. We have no furnace, use wood heat, and my water pump runs off solar power. Oven / stove are gas, biggest appliance is water heater and dryer.