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Maciek
Sep 2, 2008, 05:20 AM
I want to install a sub panel in my shed
The wire will probably run around 150'
And I will have heating and air unit in the wall that needs a 230v line
Plus 6 receptacles that were already installed there on a single line

So I'm wondering what kind of a cable do I run to the sub panel?

donf
Sep 2, 2008, 05:33 AM
First, you need to get the Amperage ratings for both the heating and AC.

Once you have an approximate amperage, you can determine your total load. There will be a voltage drop consideration because of the 150 ft. run of cable.

Also, are you planning on 15 or 20 Amp outlets? I would suggest 20 amp. Pleaseinclude lighting, inside and out.

You should be using GFCI protected outlets.

Maciek
Sep 2, 2008, 06:27 PM
The unit requires 30 amp circuit and the outlets are going to be 20
Though I just though of it and there is going to be a 1/2 bath and single sink kitchenette (sp?) in there too so I know I need a separate 20 for that plus two regular fans

thommyschnak
Sep 2, 2008, 07:50 PM
A KITCHENETTE IN YOUR SHED! This is starting to sound like a cabana house...
Well based on the combination Heat/AC, the counter outlets, lights, and what every good kitchenette needs, a refrigerator, you will need a minimum of a 60A line to your "shed".
As far as what Don mentioned about voltage drop, if you use #6 copper, at 240V, with a 150' run you will get an allowable 5% voltage drop, and there is no need to increase wire size for a 60A, 240V circuit.
If you plan on burying a conduit to this shed I would recamend at least a 1 1/2" PVC conduit, also don't forget your minimum required ground size will be #8.
Let me know how you make out, or if you need any additional help.

Maciek
Sep 3, 2008, 07:41 PM
Well the kitchenette is an additional option that might/might not be there I just want to future proof it, plus the shed will act as an office

So I can run #6-3 with ground to the sub panel with a 60A breaker and it will be enough?

I also have another question, there is already a sub panel box in another part of a house
It has three 30A breakers in it, they are for a heat and a/c unit, water heater, and a clothes dryer. I believe that the cable that runs from the main box is 10/3 w/o ground (I believe, it might be #8 but I'm not sure I'll check tomorrow) with a 50A breaker on it,
Will that be enough to run all of those things or do I have to go up in wire size?

Maciek
Sep 4, 2008, 04:22 PM
I checked it out and it is a 10/3 wire, so I guess I have to change it?