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100A subpanel wire sizing - help please

Marctrees

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Hey All!

My Googling gives me unsure answers, so Im coming to the Experts here.

This is all about I am building a very close but detached shop, need to power it.


Currently have mobile home w 100A panel in house.

Fed from pole 1' from house, from a 100a Breaker old tired disconnect on that pole, next to Meter.

Building a shop that will have it's panel located 30' of conduit path from that pole., I definitely want to feed it from that pole, NOT from the existing house panel.

Large wood deck (open newly built framing, not yet decked) exists immediately adjacent to house, adjacent to shop, so 1' from this pole.

Plan on Sch40 PVC strapped to underside of deck framing for entire route, no underground need, all structures RIGHT next to opposite sides of deck, w framed deck in between.

Deck less than 1' above grade, being built now, fully framed, not decked yet so all accessible from topside, till I run this "rough in" pipe.

Shop not yet built, in near future, God willing, but need to run the pipe now.


Now on to questions - What Hot, N, and Ground sizes do I need ? (Prefer CU, not AL)

What pipe size?

I want to go small as possible, my bend total will be way less than allowed max, LB's at both ends.Thing is I need to make a few heat bent kicks to stay snug to deck framing, and would rather bend smaller than oversize.

Not worried about the pulling, no problem

Lastly, I want to replace the Disconnect on pole, old, crusty, breaker been overheated from old under torquing.

100A Service size to feed both structures is MORE than enough for this project

So the mobile home has one panel, the shop will have a second one, both 100 main in those two panels.

Can someone point to a stock # (hopefully widely available, not obscure)
Of Disconnect to put next to the meter to feed these two 100A panels please?

Definately prefer SqD QO.

So- Conductor H,N, + G sizing, pipe sizing, and Disconnect info.

O, and no permit or Inspector, very rural TX, but still want to do right and comply to NEC.

I was a Master and Contractor for years in MN, but left it 20+ yrs ago, brain has gotten tired since then.

What you Pro Guys say, I will do.

Sberry, Wylies, others?

Thank you Gentlemen, and keep yer feet and hands dry !!! Marc
 
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wyliesdiesels

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Well u could go with an all in one sq D meter main. This would give you one main disconnect and then space for branch breakers. U would then put in 2 double poles to feed your house and shop. You would have to have the PoCo disconnect the drop and then have them move the meter over to new panel.

I looked through SQ Ds catalog and didnt see any service rated panels with just 4 spaces but I may have missed it.

As far as wire, u would need #3 cu or #1 al. so 3-3-3-8 with 1 1/4" conduit or 1-1-1-6 with 1 1/2" conduit

u will need 2 rods at the shop as well as an isolated neutral bar in the subpanel.

What size and # of conductors do u have feeding mobile?
 
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Marctrees

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Wylie - Spent some time starting to look into those Meter/Panel combo things.

Wow, that has sure changed since I've been out of the game.

OK, so Im gonna look into and consider that, but still, please comment on my option in post #3.

Thank you, Marc
 

wyliesdiesels

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OK, everything makes sense. Thank you.

I didn't plan on changing the meter can, it is in fine shape, other than putting in longer load side wires to the new disconnect.

Other than the can being excessively large, any reason why I could not use this, and plug on 2 QO 2100's?

Marc

https://www.zoro.com/square-d-load-...tofJtP0gTNNwOdlQOGPOAMq2lFzTcfC-q5BoCLqnw_wcB

No reason why you can't use that panel.

The only reason I can think of why that panel may not work is if its not service rated.
 
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Marctrees

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Ok, I seems I found smaller can, a SqD stock # for what I want, but it ?seems? to be discontinued.

QO12M100RB

https://www.google.com/search?q=QO1...7YMKHZPZDxIQ_AUICSgA&biw=1280&bih=617&dpr=1.5

There is one on Ebay, but I'm wondering if I need to worry about the obvious moisture exposure ??

http://www.ebay.com/itm/Square-D-QO...1Ph-Nema-3-Cat-QO12M100RB-BP-56-/310567569830

Also, possibly SqD currently offers a smallish panel like I want, but I cannot find it after a few hours digging.

Help ? Would you worry about the Ebay panel condition?

And, I think this is "service rated" ??

And lastly, can I plug on my 2 100a 2 pole QO breakers, or is there some limit below that?

I think I saw some SqD panels limited to 70a breakers.

Thank you again, Marc
 
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Rlapointe87

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You can use service entry cable pretty sure you need 3-3-3-5 and if you're going into conduit go bigger than you think you need if you have any bends, this stuff is pretty stiff. You could also go aluminum and save some money. Where the wire goes into the conduit it you need to strip off the outer jacket.


Sent from my iPhone using Tapatalk
 
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Marctrees

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Rlapointe - Cable is figured out, I'm looking for a certain panel now. Thank you.

Guys - Can I get like the link below, buy 3 QO 2100's, feed from meter to terminals on one as the main disconnect, it then feeds the buss, then feed off of the other two to the house, and to shop?

I feel so dumb asking this cuz I was a elect for years, but I never worked on goofy little services like this.

Marc

https://www.lowes.com/pd/Square-D-12-Circuit-6-Space-100-Amp-Main-Lug-Load-Center/3129229
 
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Marctrees

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All my yakking above simplified - I simply need to find a small as possible can size exterior service 100a panel to house a main breaker, and 2 2pole 100's to feed house, and shop.
Marc
 
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Marctrees

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Ok, I looked again at the space I have available for the new panel, how the existing meter can is positioned, etc., and see that once now I re think it, I DO have room for a normal size panel w a small amount of reconfiguring.

Do not have to disrupt exist meter base, so excellent there.

Gonna get the panel below, and once again, Zoro has best price.

Gonna call power co to confirm I'm 'OK.

Sorry to have been weird wanting the tiny panel can.

Marc

https://www.zoro.com/square-d-load-...g35&utm_content=12619775&utm_campaign=2470763
 

tyme2par4

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While you are calling the POCO, ask them if they will upgrade you to a 200A service. Many of them will do the upgrade a no charge if you are adding a load (new shop).
 
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Marctrees

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tyme - Great idea.

In my case we have a 1200ft sq doublewide home, a very private but small residential lot, and gonna be building the 1200 ft sq pole building one man no business shop.

Everything considered, no need, no advantage to upgrade to 200.

But good point, thank you, Marc
 

tyme2par4

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There may be no need now, but who knows in the future. If they don't charge you, you might as well get it done.
 
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