Yet another subpanel feed question. What's wrong with this?

While researching my impending connection of 100amp 220v power from my 200A main panel to a 100A panel in my detached garage, I found out SE-R cannot be run underground through conduit.

The situation:

Approximately 60' of the run from the main panel is through the basement (25') and crawlspace (35') then it is underground about 60' with two 45deg turns to get under a brick walkway to the garage.

The Plan:

Run 2-2-2-4 SE-R (Type SE Cable Style SER Type XHHW) from the main panel through the basement and crawlspace to a junction box on the exterior wall.
Here's the tricky part: Cut the sheathing and remove the aluminum ground from the SER for the run in the conduit underground to the garage. Since the individual cables are xhhw rated, they can be run underground in conduit...correct? For the ground, I will use a cu/al polaris connector to splice #4/6 copper from the garage to the aluminum ground that runs inside to the main panel. (Of course I also have the proper local panel (garage) ground with an 8' 5/8's Cu bar and the subpanel neutral unbonded.)

Please tell me if there is anything wrong with this?
Fire away...

Cheers and thanks for the help!

-Stump

are the individual conductors inside the cable marked? they usually arent which means you cant install them in conduit. Why not just use individual conductors and conduit the entire way?

Should be #1 aluminum not #2

SE-R cable is not rated for underground use, with or without a conduit. You can use either USE direct bury cable, or individual THWN conductors in a conduit.

MRB, thank you for pointing that out... had they been individually labeled, then it would have been kosher (maybe not necessarily for 100 amps). Even though the individual cables are XHHW rated, they aren't individually labelled so not allowed to be run.

I will likely use THWN copper cable straight through... I can use 3 #2 wires for the two hots and neutral and a #6 for the ground, right?

#2 AL SER isn't gonna cut it for 100 amps, you'll need 1/0. You'll need a real supply house too, I doubt HD/Lowes carries it.

Aceman said:

#2 AL SER isn't gonna cut it for 100 amps, you'll need 1/0. You'll need a real supply house too, I doubt HD/Lowes carries it.

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Copy that, I found an electrical supply place about a mile from my house. I prefer to support local businesses as much as possible. They have #2 Cu THWN for .94/ft and #6 Cu THWN for .38/ft.
I am planning on running this through conduit from the main panel all the way to the sub panel.
Is there anything else I'm missing?
I was thinking it might be easier to run the wire through the conduit to the garage first then assemble the conduit piece by piece in the crawl space etc.
Any tips on pulling wire?

StumpFJ40 said:

Copy that, I found an electrical supply place about a mile from my house. I prefer to support local businesses as much as possible. They have #2 Cu THWN for .94/ft and #6 Cu THWN for .38/ft.
I am planning on running this through conduit from the main panel all the way to the sub panel.
Is there anything else I'm missing?
I was thinking it might be easier to run the wire through the conduit to the garage first then assemble the conduit piece by piece in the crawl space etc.
Any tips on pulling wire?

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dont know if it matters to you, but code requires the conduit be installed as a system then the wire pulled through.

mrb said:

dont know if it matters to you, but code requires the conduit be installed as a system then the wire pulled through.

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I did not know that... anyone know why that is? is there an issue of the wet glue damaging the cable?

StumpFJ40 said:

I did not know that... anyone know why that is? is there an issue of the wet glue damaging the cable?

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its not glue since it applies to metal conduit as well. I think its either the wire getting damaged by installing in that fashion, or ensuring wire can actually be pulled through the conduit as installed.

mrb said:

dont know if it matters to you, but code requires the conduit be installed as a system then the wire pulled through.

Click to expand...

mrb said:

its not glue since it applies to metal conduit as well. I think its either the wire getting damaged by installing in that fashion, or ensuring wire can actually be pulled through the conduit as installed.

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Ok, and how in the hell are they going to know? They show up to inspect and the conduit and wire are there for the rough in, unless you told them you did it in sections, I don't see how they could tell.

William....

W-Cummins said:

Ok, and how in the hell are they going to know? They show up to inspect and the conduit and wire are there for the rough in, unless you told them you did it in sections, I don't see how they could tell.

William....

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first its about doing work to code, not seeing what you can get away with.

to answer your question, one scenario would be an underground conduit. It will be inspected before backfill. The wire wouldnt be pulled at this point.

probably not a big deal for the OP, it was just something worth mentioning.