Underground to Indoor Wire Transition

[Augus7us]

Hey All,

Because of where my breaker box is in the house I'll have to transition my underground cable to indoor cable for the last 30 feet of the run, to get power to my shop.

Where the wire transitions I was going to put a disconnect box, but the supply house said because it was 100amps it was going to be $260...

I'm willing to spend that but I thought I would see if there was a cheaper solution. I don't need the disconnect, I already have one in the breaker box I'm putting in the shop.

Thanks!

-Clint

 

[bmwpowere36m3]

Can't you use a regular box to make the transition inside the building?

 

[nh_yota]

Junction box and split bolt or polaris connectors.

 

[pattenp]

Use a large PVC junction box. As said you can use split bolts or Polaris connectors or splice reducers to make the splice. I assume you are connecting the same type wire together, copper to copper or aluminum to aluminum.

 

[wyliesdiesels]

What type and size of wire did you use?

The disconnect is overkill.

Just use a box as said above!!

 

[Augus7us]

I haven't used any wire yet. It will be 2-2-2-4 AWG aluminum underground cable connecting to the same gauge aluminum cable for indoors.

Is this what you all are referring too? If so are you saying I would need four of these and just connect each pair of wires, tape them up and close up the box? They don't mount to box or anything?

https://www.platt.com/platt-electri...ers/NSI-Tork/ITO-1-0/product.aspx?zpid=292314

I agree the disconnect is overkill but the price difference between the two may end up negligible.

Thanks

-Clint

 

[Bretny]

I did exactualy what your trying to do in #2 alu also. I used a large metal junction box inside with proper bolt on connectors. Its been 4yrs.

Have you checked the price on a home depot disconnect....here.
https://www.homedepot.com/p/GE-100-...r-General-Duty-Safety-Switch-TG3223/202978655

 

[rlitman]

I did exactualy what your trying to do in #2 alu also. I used a large metal junction box inside with proper bolt on connectors. Its been 4yrs.

Have you checked the price on a home depot disconnect....here.
https://www.homedepot.com/p/GE-100-...r-General-Duty-Safety-Switch-TG3223/202978655

Depending on how you will run it, another option would be an outdoor disconnect box. That's about $10 more.

https://www.homedepot.com/p/GE-100-...-General-Duty-Safety-Switch-TG3223R/202978656

 

[wyliesdiesels]

I haven't used any wire yet. It will be 2-2-2-4 AWG aluminum underground cable connecting to the same gauge aluminum cable for indoors.

Is this what you all are referring too? If so are you saying I would need four of these and just connect each pair of wires, tape them up and close up the box? They don't mount to box or anything?

https://www.platt.com/platt-electri...ers/NSI-Tork/ITO-1-0/product.aspx?zpid=292314

I agree the disconnect is overkill but the price difference between the two may end up negligible.

Thanks

-Clint

With #2 al, you will be limited to 90a.

And yes those are the correct connector.

 

[Augus7us]

I was actually at HD looking at this stuff yesterday and they didn't have any disconnects over 60amps at the store. The outdoor one is what i would need but even at $100 its still over half what the supply house was.

With #2 al, you will be limited to 90a.

And yes those are the correct connector.

Yeah, in my other thread I was stating I was going to use copper to get the full 100amps but everyone here is saying just use AL and save money and when I called asking for 3AWG copper the supply house said they didn't have it and just use AL and save money. Since I probably wont notice the 10amp loss I'll take the savings I guess.

-Clint

 

[Augus7us]

Let me ask you guys this, would I be ahead to just run indoor rated cable the entire run and put it in conduit for the stretch running underground between the house and shop?

-Clint

 

[rlitman]

Let me ask you guys this, would I be ahead to just run indoor rated cable the entire run and put it in conduit for the stretch running underground between the house and shop?

-Clint

Underground conduit is a wet location. What sort of cable are you planning on using?

 

[wyliesdiesels]

Let me ask you guys this, would I be ahead to just run indoor rated cable the entire run and put it in conduit for the stretch running underground between the house and shop?

-Clint

Indoor cable such as?

If its not rated for underground use then its a no go. The moisture will corrode it. Yes even in conduit..

 

[Augus7us]

Ok I thought that might be a no go.

I'm not at home so I don't have my notes with me. I was just going to use 2224 underground feeder, sorry I don't remember what the cable type was the supply house had.

I ask because I read somewhere that you cannot run underground cable indoors because the jacket is not fire rated or something to do with fire. I have to run about 60' underground to my house then about 30' in my basement to my breaker box on the other side of the house. What I read said that you could run 6' of underground in the house to your box, but further than that it needs to be indoor rated SE cable to the breaker box.

If I could run the underground cable all the way from the shop to the side of the house with the breaker box I would, unfortunately that is not an option.

My guess is most just run the underground cable indoors? Am I overthinking this?

-Clint

 

[wyliesdiesels]

Ok I thought that might be a no go.

I'm not at home so I don't have my notes with me. I was just going to use 2224 underground feeder, sorry I don't remember what the cable type was the supply house had.

I ask because I read somewhere that you cannot run underground cable indoors because the jacket is not fire rated or something to do with fire. I have to run about 60' underground to my house then about 30' in my basement to my breaker box on the other side of the house. What I read said that you could run 6' of underground in the house to your box, but further than that it needs to be indoor rated SE cable to the breaker box.

If I could run the underground cable all the way from the shop to the side of the house with the breaker box I would, unfortunately that is not an option.

My guess is most just run the underground cable indoors? Am I overthinking this?

-Clint

As always, the devil is in the details. Its a little more detailed then what you described.

Underground rated wire is code permitted to be inside a building IF it has a RHH or RHW rating.

Mobile home feeder is a wire product that has both underground ratings and fire resistant ratings.

The only caveat is it does not have an outer jacket so it must be ran in conduit indoors.

URD is underground rated but not fire rated so no go indoors.

SE type cable is indoor and outdoor rated but not underground rated.

If you dont want to run conduit indoors, then use MHF outside and transition to SER inside in a large junction box...

 

[rlitman]

...If you dont want to run conduit indoors, then use MHF outside and transition to SER inside in a large junction box...

Or use the disconnect for the transition. That comes with terminals, and a nice and large box. A set of Polaris lugs plus the box will run you just as much. Or you could use split bolts and tape and save some.

 

[Augus7us]

Thank you for the detailed response wylie, I figured I was butchering what I read and you aren't joking about the details when it comes to electrical code. But I think you've given me exactly what I need to pickup and how I need to install it.

I agree rlitman, the cost of the polaris bolts and a box are going to be about the same and I like the idea of having terminals to bolt the wires to and keep everything clean in there. I really don't need a second disconnect but it'll do.

That said I'm glad I was educated on split and polaris bolts. First I've heard of them and they are going to solve a problem I had in the house, moving my security system.

Thanks again fellas!

-Clint

 

[wyliesdiesels]

Thank you for the detailed response wylie, I figured I was butchering what I read and you aren't joking about the details when it comes to electrical code. But I think you've given me exactly what I need to pickup and how I need to install it.

I agree rlitman, the cost of the polaris bolts and a box are going to be about the same and I like the idea of having terminals to bolt the wires to and keep everything clean in there. I really don't need a second disconnect but it'll do.

That said I'm glad I was educated on split and polaris bolts. First I've heard of them and they are going to solve a problem I had in the house, moving my security system.

Thanks again fellas!

-Clint

Security system as in burglar alarm?

I wouldnt use those connectors for small low voltage wire found on security systems. Theres other connectors that are way more appropriate.