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needhelp200
Feb 14, 2008, 05:03 PM
OK.. I am running a line out to my new garage. Its coming out of my 200amp service into a 125 amp sub panel with a 125amp breaker.

Question is, can I use 2224 for this. And if so can it be buried in conduit? I assume 2224 will carry 125 amp, as my thinking is it is 3 #2 wires (2 Hot,1 Neutral) and 1 #4 for grounding(2224). I assume Ill have to get #6 or 8 to run from the gnd rod back up into the euipment ground buss.

Also seen some 1113 ser I think that's what it was. Would that work better?

Does all this make sense? Will 2224 carry this load, can it be used under ground in conduit.. Those are my 2 questions. I think its 2224 AL I was looking at today. Is there a diff in AL and NON Al.? Any help will be appreciated!

tkrussell
Feb 15, 2008, 07:24 AM
For a residential 125 amp feeder, neither of the wire sizes you mention are correct.

This will need a min of #2 copper or #1/0 aluminum.

You mention 4 wire cable ,which is correct, but need to know what type of insulation the cable has to understand if it can be buried.

Typical insulation for underground is USE for direct bury, and XHHW for installing in an UG conduit.


If all you have available is #2 AL, then the feeder can only be 100 amp.

Exactly what size and type cable are you considering?

needhelp200
Feb 15, 2008, 03:00 PM
I see now. So all I need is 1/0 Al Or #2 copper. Gotcha I can handle that. I assume I will need 3 of those the same size for hots and Neutral, then most likely #6-8 for equipment Gnd. And the same for the ground rod I have to drive in at the shop.


Now I assume that they sell a reducer or something so as to get 1/0 wire into the breaker and ground buss? I have heard of people trimming off some of the outside strands in order to make it fit. Sounds like trouble to me

Lastly, I noticed in depot that there are regular ground buses AND equipment buses. Is there a difference in the 2. They looked the same to me. But Im not sure.

tkrussell
Feb 16, 2008, 06:25 AM
For a 125 amp feeder, the equipment ground needs to be a min of #6 copper or a #4 Al.

Use may use either #8 or # 6 copper to run from the equipment ground bar to the ground rod also.

Never cut strands off a conductor to make fit in a wire connector.

A panel or breaker rated 125 amp should allow #1/0 to fit. Read the data sheet on the terminations, it will list the wire range the connector is rated for.

There are crimp on wire reducers, but only available at electrical distributors, and required special crimping tools and dies to install properly.

If something does not allow a larger wire, then a mechanical lug will need to be added.

I do not know what a "regular" ground bar is. You should find two types, one is a Neutral bar, which will come with insulating mounting feet, and equipment ground bars, which are intended to be bolted directly onto a metal box using machine thread screws.