bharbwyr

Here's one thats got me stumped. Say calculations show a max load at a house service of 70A before VD exceeds 3%. If the house is already drawing a load of 50A, will a compressor that draws a running load of 20A have a hard time starting. In other words, do I need the starting Amp figures instead of normal operating load? Thanks

RIVETER

Is this a hypothetical question? 50 amps continuous load on a residence is pretty high in my estimation...unless you are AL GORE.

bharbwyr

The 4 bedroom house in question will have water heat- 19A, deep well pump- 10A?, septic pump- 6A?, poss. range/oven-30A?, water-derived heat pump- 22A and circulator- 3A, as well as basic appliances and efficient lighting. There is a 500' run from the meter, and my calc.s say 4/0 will allow 71 amps @3%VD. I realize that continuous load may be far less than 50A.

I suppose that a more common hypothetical would be a remote shop with an old existing #8 feeder, and the big motor on the new dimensional sander requires 18A normal operating load. Assuming only 20A available@3%VD, will the motor have problems starting?