Ready to build a 28 x 32 with 10 foot sidewalls. What is the basic electricity service I would need? Lights, receptacles etc. Will not be doing any heavy work just basic maintenance etc. I don't want to cut corners but don't want to put in what I don't need. Thanks
New Garage
- Thread starter blh
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billconner
Well-known member
Will you park cars there and want to charge or be able to add charging for an EV? I'm planning 240 60 amps for just what you say plus allowing to charge an EV someday or future owner.
wssix99
Well-known member
Depending on what you are doing in there, you'll need something between 50 Amps and precisely 1.21 Gigawatts.
If you don't have any special equipment in there to plan for then your EV needs are probably the limiting factor, as @billconner points out. Current top-of-the-line home chargers draw 40 Amps. If you are charging three cars at the same time, then you would need 120A, plus electricity for lights and whatever else you would be doing. In the future, you may need more power for this purpose.
Even if you are only doing light shop work, I would still plan for EV charging capability if your garage will physically hold cars. Someday, the property will be sold and in 5-10 years from now EV charging/capability is going to be a big deal when buying/selling houses.
If you don't have any special equipment in there to plan for then your EV needs are probably the limiting factor, as @billconner points out. Current top-of-the-line home chargers draw 40 Amps. If you are charging three cars at the same time, then you would need 120A, plus electricity for lights and whatever else you would be doing. In the future, you may need more power for this purpose.
Even if you are only doing light shop work, I would still plan for EV charging capability if your garage will physically hold cars. Someday, the property will be sold and in 5-10 years from now EV charging/capability is going to be a big deal when buying/selling houses.
to be specific:
48a chargers are the norm currently within the car. the "wall connector" is then wired to a 60a breaker due to NEC continuous load rules. The big boy home chargers will do 80a right now. 100a breaker rating on them.
If you plan for 40a per stall you're doing just fine. They make plenty of chargers that work together to figure out who gets what without blowing the works up.
Someone confirm for me but i'm pretty sure 2" will get you 200a no problem. Hence bury 2" now, pull in you 20a circuit for lights and an outlet. then down the line put in what ya need when you go to EV.
billconner
Well-known member
I was planning 6/3 UF cable from a 60 amp breaker to a main lug panel with 12 spaces. One and done.
Terry D
Well-known member
Im a believer in putting at least 90 amp feeders to a sub panel in something like that. It doesn't cost that much more to go from a 60 to a 90. You have to put a 100 amp panel out there anyway, because that is the smallest they make. Don't go less than 20 spaces. It will be there if you ever need it in the future.
ssffnomad
Well-known member
1) Today , go 12’ or even better 14’ high.
2) ) install extra oversized conduit for future
2) ) install extra oversized conduit for future
wyliesdiesels
Well-known member
6/3 UF will be far more expensive than #2 al MHF....
billconner
Well-known member
Doesn't MHF require conduit? For a unheated building purely for storage, with another shop space, and a 70 years old, seems unnecessary. I may not put a slab in it even, just gravel. I'd run a couple if 20 amp circuits if it weren't for probability of EV chargers.
MHF is direct burial rated. https://www.southwire.com/wire-cabl...-cable-with-alumaflex-brand-conductors/p/BW19
then you get into needing a single means of disconnect for a remote building. can't just slap 2 - 20a's in from my understanding.
wyliesdiesels
Well-known member
It requires conduit when indoors but using conduit all the way is best.
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Syberia
Well-known member
Conduit is cheap (or was, pre-COVID, and still is compared to wire), much less likely to get damaged, and makes it easy to replace whatever is inside later.
mike93lx
ALLIANCE MEMBER
And when above ground outdoors. At what depth does that trigger? 18" down?
nadogail
Well-known member
If you want to have exactly what you need and nothing extra, you will need an exact load study to make an exact plan so that your material purchase will be optimised.
wyliesdiesels
Well-known member
I don't understand your question. Are you asking for burial depth requirements? It varies... heres the chart
mike93lx
ALLIANCE MEMBER
I was highlighting that conduit is required outdoors as well, above a certain depth because your post only mentioned conduit indoorsI don't understand your question. Are you asking for burial depth requirements? It varies... heres the chart
I have a question about your chart, which if I am reading it correctly is very helpful. So direct burial, 200 Amp, 240 Volt service ran under a garage only needs to be 18 inches below what exactly? 18 inches below the thickened edge of a monolithic slab? So if the slab is 12 inches deep, 10 inches below grade, the wire would need to be 28 inches deep total? Or 18 inches below grade total? Does the slab count as "cover"?I don't understand your question. Are you asking for burial depth requirements? It varies... heres the chart
Terry D
Well-known member
It is from final grade, so the thickness of the concrete counts. The minimum cover requirement is different than the trench depth requirement. The minimum cover is from the top of the final grade to the top of the conductors or conduit. The trench depth will also include the diameter of the conductors or conduit.
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alfredeneuman
Well-known member
A separate structure like this is required to have either main breaker panel or a disconnect on the building ahead of the panel
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Or a box with 6 spaces or less, correct?
Either way, something trenched at least 36 inches can be under anything, right? Even O'Hare's runway?
wyliesdiesels
Well-known member
No the panel does not need to have 6 spaces or less.
You just cant have more than 6 breaker handles without a main disconnect.
Sorry, I guess that's kinda what I meant. But that leads me to another question. If the handle count is what code requires, what about handle ties as a way around it? Lets say you have a garage with 6 handles and you want to add another circuit. Obviously, the correct way would be to replace the box with a main breaker. But lets say you are a cheap *******, and want to just replace a single breaker with a tandem. If you got a handle tie so you still only have 6 throws to disconnect everything, is that legal?
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Terry D
Well-known member
Its all about the amount of throws. 6 throws maximum. A single pole is one throw. A 2 pole is one throw. A tandem is two throws
But is a tandem two throws if the handles are tied together? Or two single poles with the handles tied together?
Terry D
Well-known member
You can not tie the handles together on a tandem.
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alfredeneuman
Well-known member
Any job worth doing is worth doing right.
Forget the Mickey Mouse workarounds any just bite the bullet and buy the right things the first time.
Forget the Mickey Mouse workarounds any just bite the bullet and buy the right things the first time.
You absolutely can tie the handle together on a tandem. Every breaker manufacture I know makes a handle tie for its tandem breakers. Eaton even makes a handle tie to tie 4 regular single pole breakers together.
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I do not believe this would qualify as a Mickey Mouse workaround. You would be using manufacturer supplied products to do exactly what these products were intended to do. A MM workaround would be something like a non approved handle tie, or to double tap a breaker not designed to be double tapped.. Nothing about using a handle tie would in any way make the situation unsafe. The only draw back would be that if one of the circuits tripped, it would also trip the tied in circuit as well. The way I see the handle restriction is the code writers wanted to make it as quick as possible to switch all the power off in an emergency.
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Terry D
Well-known member
I stand corrected. I dont see any reason for tieing handles together on a tandem breaker other than ******* a inspector off
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I agree I don't think I would ever tie the handles together. I think the only reason being would be to skirt the 6 throw rule. Just spit-balling here, but I guess you could tie something like your sump pump breaker to your bedroom lights, so if the sump tripped, it would also trip your lights and you would have to go into the basement to figure out what happened, avoiding a flooded basement. But I have an alarm on the sumps battery backup. Learned to have a battery back-up the hard way.
alfredeneuman
Well-known member
Maybe unorthodox would be a better term than Mickey Mouse
Handle ties are intended to gang together multiple single pole breakers of a mulitiwire branch circuit and not listed for the purpose you propose.
(BTW, the "double tapped breaker" you pictured is a SqD QO and the terminal is listed for 2 wires of the same size.)
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ROBZ71LM7
Well-known member
Given that Electric cars are on the rise I would do 90 amp service, not that much more money. Tesla chargers for full output require 60A service and have 48A continuous draw if I recall correctly.
that is the max. realistically 6.6kw per stall is more than enough for most people.
ROBZ71LM7
Well-known member
Don't we want the max in our GJ world?
I say that tongue in cheek. When you say the max do you mean at the max setting on the charger or that they are really don't pull 48A? I know they can be set for whatever size service you have. Thanks.I just grabbed the first double tapped breaker picture google pulled up that was clear.
Don't we want the max in our GJ world?
the max setting is for a 60a breaker - 48 continuous. can set it down by 5amp all the way down to 15a if i recall correctly.
in all tesla's right now the max they will take is 48a cont.
the ford F150-lightning will have an 80a max. 100a breaker IIRC.
but backing up a minute and thinking higher level. at 7.7kw(32a cont) you're looking at roughly 105 kwh delivered for a 14 hour charge cycle. that is a **** ton of power for general use. Car commuting an hour each way more than covered by that. Even the F150 lightning could drive an hour each way and be charged up by the 7.7kw
for the guy knowing he will run a jobsite from his F150 lightning with the 200kwh pack then he needs the 19.2kw big ***** charger. Even with the big one it's still 10 solid hours at 19kw deadish to full.
so in short: 40a per stall breaker size is more than enough for pretty much everyone. 30a would cover a large large chunk of the population. but this is GJ so pull in 100a per stall just to be safe.
Side note: they make a really nice unit that takes a 40a breaker, has 32a cont rating but has 2 cords coming out of it. It lets 2 cars be charged off that single line. for the vast majority of commuters this setup is the one i'd suggest.
Store Products | Enphase
alfredeneuman
Well-known member
No. You just grabbed the first breaker that had 2 wires going to it.
That is not a double tapped breaker