Garage/Shop electrical service sizing

Honestly for what you're talking about, a 40 circuit panel with a 100a breaker in your main panel and 2/3 copper uf/seu from the main panel would be a lot less hassle and money. None of the things you have listed other than possibly the compressor will ever pull more than 20a each.
 
Ron said:
Directional boring is cheap....
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When I was trying to figure out the run to my shop, I looked in to directional boring. Had two guys come out and quote. First was ten bucks a foot (so five grand). Second guy didn't want the job (after he saw what area of the county I am in) but said it would be twelve bucks if he were to do it.
 
Get the shop it's own service.
I don't don't know the size ... never bothered to look. here when I bought the place.
I have been welding and heard the compressor kick on with no issues.
Mines like 14 bucks a month and well worth it.
Your wife will hate you if you don't.
 
Ron said:
Based on a situation a friend finds himself in I've sworn off to giving advice online in public.
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QFT

I will say that Duke treats the meter base as customer equipment no matter what, a 400a intermittent costs about $750 on it's own, and voltage drop is voltage drop. If you're on the same transformer, you're going to have some when big loads come on.
 
shawn said:
QFT

I will say that Duke treats the meter base as customer equipment no matter what, a 400a intermittent costs about $750 on it's own, and voltage drop is voltage drop. If you're on the same transformer, you're going to have some when big loads come on.
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So if I am responsible for the cost of the meter, the difference is to pay $750 up front for a 400A meter, or buy a second cheaper 200A meter but then pay the $14 every month for dual service which will break even in a few years?
 
Fabrik8 said:
I think the main feed to the house runs right where the (detached) garage is going to go, so that will have to get moved or something like that.
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If your current service is in the footprint of construction, a new service will need to be installed before anything else happens.

Your first call needs to be to Duke Energy to get an engineer sent out to determine what's existing, and what they can offer you.

I wouldn't make ANY plans or assumptions until you at least get that far
 
Fabrik8 said:
So if I am responsible for the cost of the meter, the difference is to pay $750 up front for a 400A meter, or buy a second cheaper 200A meter but then pay the $14 every month for dual service which will break even in a few years?
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It's most likely $20 a month since it's a detached garage. Either way, unless your house is 5000sf I really don't see the need for a 400a panel upgrade.
 
Fabrik8 said:
So if I am responsible for the cost of the meter, the difference is to pay $750 up front for a 400A meter, or buy a second cheaper 200A meter but then pay the $14 every month for dual service which will break even in a few years?
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Plus a few thousand in electrician and permit fees, assuming the meter base stays in the same spot.
 
CasterTroy said:
If your current service is in the footprint of construction, a new service will need to be installed before anything else happens.

Your first call needs to be to Duke Energy to get an engineer sent out to determine what's existing, and what they can offer you.

I wouldn't make ANY plans or assumptions until you at least get that far
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Yep, I'm going to get in touch with an electrician and also Duke, to explore options.

braxton357 said:
It's most likely $20 a month since it's a detached garage. Either way, unless your house is 5000sf I really don't see the need for a 400a panel upgrade.
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If my existing service isn't going to handle the garage load, I will need a new drop from the transformer, and can then do whatever is needed. Unless I'm totally missing what you're saying, and could get by with sharing the existing 200A service between the house and the garage.
I'm just not sure the math makes sense there, but I'll have to add the loads up and see. Realistically, it would need to handle both HVAC systems, the house water heater, some lights, the compressor (if it kicks on from tank pressure), and the lift (or welder) at the same time, plus minor other loads and some margin. Basically, everything that is automatically controlled needs to be able to run at once, plus the optional things like lift or welder (either, not both). Maybe washer and dryer too.
It's not a good compromise to cuts things too close (for load capacity) if my wife can't do laundry just because I'm working in the garage, for example.
 
shawn said:
Plus a few thousand in electrician and permit fees, assuming the meter base stays in the same spot.
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Yeah, that's probably a given no matter what happens. That's what I'm exploring these things, to look at order-of-magnitude for electrical costs.
 
braxton357 said:
It's most likely $20 a month since it's a detached garage. Either way, unless your house is 5000sf I really don't see the need for a 400a panel upgrade.
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CEMC used to be $14/mo. Now base bill is $36 for a detached. Break even for me was about 4.5 years.

Sent from my SM-G930V using Tapatalk
 
Fabrik8 said:
Yep, I'm going to get in touch with an electrician and also Duke, to explore options.



If my existing service isn't going to handle the garage load, I will need a new drop from the transformer, and can then do whatever is needed. Unless I'm totally missing what you're saying, and could get by with sharing the existing 200A service between the house and the garage.
I'm just not sure the math makes sense there, but I'll have to add the loads up and see. Realistically, it would need to handle both HVAC systems, the house water heater, some lights, the compressor (if it kicks on from tank pressure), and the lift (or welder) at the same time, plus minor other loads and some margin. Basically, everything that is automatically controlled needs to be able to run at once, plus the optional things like lift or welder (either, not both). Maybe washer and dryer too.
It's not a good compromise to cuts things too close (for load capacity) if my wife can't do laundry just because I'm working in the garage, for example.
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The things you're talking about are in hundreds of thousands of attached 2 car garages across the country being serviced by the same 200a panel as the house or off a subpanel. Your "5" hp compressor will be drawing under 20a, your mini split will be pulling under 10a even at start up, your lighting will be LED so that's negligible, I've never personally seen a lift with larger than 2hp 220v, so again 15a. A 200a size mig will pull in the low 20s maxed out.


All that to say, if you were somehow able to use all of the tools in your shop at once, your home heat pump was in defrost with the strips running, your water heater was electric and heating, and you had the dryer running, youd still be well under 200a total..
 
braxton357 said:
The things you're talking about are in hundreds of thousands of attached 2 car garages across the country being serviced by the same 200a panel as the house or off a subpanel. Your "5" hp compressor will be drawing under 20a, your mini split will be pulling under 10a even at start up, your lighting will be LED so that's negligible, I've never personally seen a lift with larger than 2hp 220v, so again 15a. A 200a size mig will pull in the low 20s maxed out.

All that to say, if you were somehow able to use all of the tools in your shop at once, your home heat pump was in defrost with the strips running, your water heater was electric and heating, and you had the dryer running, youd still be well under 200a total..
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If that math works out, then it would be a lot more convenient to not run a new service. Might be good motivation to ditch our electric water heater and go gas tankless, because that would still likely save a lot of money in electrical service costs.

It definitely is a 3.5HP lift though. It's rated at 37 second rise time, so that would explain the bigger motor (kind of like the 5HP Shockwave models that Rotary has). I could go cheaper and get a China lift with a 2HP motor, or go more expensive and get a Rotary with a 2HP motor, but I like my choice... It will be running so infrequently that I'm not too worried, unless everything happens to be timed badly and running at the same time. I'll never be running the lift at the same time as a welder, etc,. so there's some minor logic involved there.

I still haven't had time to make a spreadsheet for load estimates.

I did find out that my dual-fuel range (electric oven only) only needs a 30A breaker instead of the existing 50A breaker, so that's a start.
Dryer is on a dual 30A, Gaspack on a dual 40A, water heater on a dual 30A, sump pump on a 20A, washer on a 20A, got rid of the stupid jet tub, got rid of the disposal. Hmm..
 
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You're really making this more of a thing than it is. If you have 200a at the house just run a 100a feed off of it. You will never touch either of them. I wouldn't want a new service if I could get away with it. $20/mo is still $20/mo. It pisses me off at work to see that monthly access charge on some of our buildings if we didn't use any electricity at that building, but I'm too cheap to pay for directional boring so maybe it's just me :flipoff2: @Ron
 
The $25-30/month power bills on my shop piss me off because they should be $5-10/month. If it were not so far from the house, it would be running off of the 200amp service in the house, but the pricey wire and inevitable voltage drop combined with large loads made it a no-go.
 
awheelterd said:
You're really making this more of a thing than it is. If you have 200a at the house just run a 100a feed off of it. You will never touch either of them. I wouldn't want a new service if I could get away with it. $20/mo is still $20/mo. It pisses me off at work to see that monthly access charge on some of our buildings if we didn't use any electricity at that building, but I'm too cheap to pay for directional boring so maybe it's just me :flipoff2: @Ron
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I totally agree, I'm going to roll with it if it makes sense for capacity and it's not super tight for margin. Gotta relocate the service from where the slab is going to go though, so we'll see what makes sense. And try to keep the wife from doing too many wife things while I'm in the garage doing to many garage things. I'm not going to get a second meter though, I'd rather pay up front and get the 320A/400A meter if we need extra capacity instead of having separate meters that will be 25 feet apart.
 
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Just spoke with the electrician that I've been waiting to hear back from. He asked me lots of questions and says the existing 200A service should be perfectly fine. So now I have an electrician, probably. Also talked about relocating/replacing the house panel, but that's a different ball of wax.

Have a work request to be contacted from an engineer at Duke Energy United to figure out the process to get the main feed moved in the yard once we know exactly where the slab is going to go. I guess Energy United directly handles their own infrastructure, even though the easement and everything is owned by Duke, because I'm an Energy United customer.


Kinda glad I don't have to mess with a 320/400A meter and feed and all the logistics involved with that..
 
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Random question, because I'm still have a hard time tracking down the right people:

Is a Duke overhead distribution easement (small poles) centered on the pole path/spline?

I've got 3 different plats and 3 different locations of where the easement is drawn, and none of them are centered on the pole lines. Polaris shows it as being centered on the poles (easement overlay on the satellite view), which seems to agree with what Google may say about how power easements usually work. Makes sense, it's easy for Duke to track and record an easement that is centered on the pole line.

Anyone have insight, until I eventually track someone down that has a real answer? Why is this so difficult?

I'm planning on asking the Energy United engineer when he gets in touch with me eventually (sounds like something he should have a good handle on), but I may have just spotted a fatal flaw that may completely change where I have to put the garage.
 
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They typically go from center conductor. So, 10’ (or more depending on the service type and voltage) on either side of the center conductor.
 
Fabrik8 said:
That sucks even more, because the pole tilts the wrong way. :D

I get your meaning though.
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Any large trees near by? Would be a terrible accident if one got cut down and took out the pole. This of course after you pull the original plot showing where the pole needs to be put back up.
 
Futbalfantic said:
Any large trees near by? Would be a terrible accident if one got cut down and took out the pole. This of course after you pull the original plot showing where the pole needs to be put back up.
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you might away with that on a service line. Highly doubt it on a distribution line. Remember, other people down the line depend on that power. :)
 
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