Electrical help: Running a new 220 line?

[vtcruiser60]

I am sure I'll forget to turn them both off at some point in the future and wish I had run the subpanel....but cash is tight.

Anyway...I put the volt meter up to the receptacles last night and both ran at 240. No drop between lines. Perfect....

Thanks again for the help.

 

[-Spike-]

You won't see a drop without a near-capacity draw. I doubt you'd have a significant voltage drop, but if you want to test it put a meter on the line and watch it while you trigger the welder at it's highest setting for a few seconds. It will drop, but shouldn't be much- I think you're OK if you're within 10% of rated voltage.
I did this test with a 50 foot 14 AWG extension cord feeding a 15A chop saw, and saw the voltage drop from 115v to 90v. My buddy was wondering why his saw was bogging. The saw didn't last much longer, and we figured the cord was to blame. The voltage drop will cause the appliance to draw more current and burn itself up.

-Spike

 

[semlin]

this seems to be the right place to ask this question since it is very close to vtcruiser's. If I have a two pole 40 amp dual pole breaker on my house box that covers the cable running to the garage, and there is a small breaker box in the garage with three 15 amp breakers, one for lights and two for different sets of wall plugs, is there any reason why I can't add a two pole 20 amp breaker to the small box so I have a 220 amp citcuit out there? I can't actually see the wire since it is in conduit but whatever it is should handle 20 amps shouldn't it? I just bought a 3000 watt 230 v blower/heater for the garage and I was thinking I'd need to run a separate cable but now I'm thinking that the heater is only going to draw 13 amps at 220v so i should be good?

and while we are there, the box in the garage has no groundwire, but the cable to the house is in metal conduit. Is that an acceptable ground? It was built in 1998 and it sure looks like this thing was built to code.

 

[fj40charles]

this seems to be the right place to ask this question since it is very close to vtcruiser's. If I have a two pole 40 amp dual pole breaker on my house box that covers the cable running to the garage, and there is a small breaker box in the garage with three 15 amp breakers, one for lights and two for different sets of wall plugs, is there any reason why I can't add a two pole 20 amp breaker to the small box so I have a 220 amp citcuit out there? I can't actually see the wire since it is in conduit but whatever it is should handle 20 amps shouldn't it? I just bought a 3000 watt 230 v blower/heater for the garage and I was thinking I'd need to run a separate cable but now I'm thinking that the heater is only going to draw 13 amps at 220v so i should be good?

and while we are there, the box in the garage has no groundwire, but the cable to the house is in metal conduit. Is that an acceptable ground? It was built in 1998 and it sure looks like this thing was built to code.

Do you have room to install a double pole 30 amp breaker in your subpanel instead on installing 2 individual 20 amp breakers?

Not sure what your code is, but some places may allow you to use the metal conduit as the ground. I personally would feel safer having a dedicated ground wire to ground the junction/receptacle box.