Installing Electric in pole building soon

[Nhrafan26]

I am going to be rough wiring my new garage soon.
I have decided to go with metal conduit and metal boxes for ease of changing things around and durability.
Questions: What's the wire I should be using for the job? THHN? I am already going with almost all 20A circuits (12G) except probably the lights and maybe a few light duty outlets in an office area.
Also a question is how to do a load calculation on a workshop?
Basically I know what my air comp is rated at, I can check my welders, I have a PTAC unit that I know the draw of but otherwise how to include all other lights and outlets to get a true rating of what size panel I'll need.
I was already planning on going with a 200A panel but starting to think this is possibly overkill? I will be adding in a mobile home furnace within 2 years and IF I get a good deal on a lift that as well. I have a Medium size TIG, a smaller MIG and another welder none of you probably ever heard of (well maybe some canadians) but will NEVER be using more than one at a time.
I know just giving the equipment does absolutely nothing but does that sound close to needing a 200A panel?
Besides that I need to talk to PP&L and find out what my options are for the them extending power to the garage...

 

[simpler=better]

I'd just run all 12g-you can probably get cheaper pricing when you buy 500ft rolls than piecing together 14&12 branches.

Calculate which machines you will be running at the same time, ex:
Air compressor & plasma cutter & heater in the winter...
or
You're welding, a buddy is running the plasma cutter, in the summer with the AC on...

Rule of thumb around here, a 100A panel is probably fine.

 

[bmxdad]

100 amp panel should be more than enough for a garage, unless your running a business out of it. I ran my conduit under the slab, if you haven't already poured it something to consider. Great time saver. Use conduit that is bigger then you actually need.

So how big of a garage is this?

 

[Nhrafan26]

100 amp panel should be more than enough for a garage, unless your running a business out of it. I ran my conduit under the slab, if you haven't already poured it something to consider. Great time saver. Use conduit that is bigger then you actually need.

So how big of a garage is this?

The garage right now is 30'X40'X12'
I have not poured the floor yet, waiting until spring to do that so I have time to get everything set up like pots for pulling things, possible drain, running water lines and conduit etc. etc.
The link to my build is in signature.
Not running a business, just an automotive hobby with occasional backhoe repair, regular maint. and home improvement here and there.

 

[wyliesdiesels]

Whats the HP rating on the compressor?

And if u havent poured the slab yet make sure u do a UFER ground.

 

[Fallon]

Will more than 1 person be working at a time? Really how many tools can you operate at once if it's just you? Worst case scenario I can figure for my or many other shops is compressor, plasma cutter, lights, stereo, fridge & possibly a fan for the heater (assuming wood or gas heat not electric). Game changes a bit more if you have multiple people working.

50@ service worked for my shop (Miller Maxtar 200 welder, 30@ plasma cutter + 5hp compressor, etc.) & I never blew a breaker, well at least a main breaker. I did just upgrade to 125@ service as I put in new conduit out to the barn/shop as part of a photovoltaic system install. Solar guys pulled the extra wire through the conduit for just the price of the copper & the breaker box.

Some pretty jenky stuff in my shop from the previous owner, most notably a 150@ breaker at the house "protecting" wire rated to only 50@ (there was a 50@ breaker out at the barn/shop though providing some protection).

I'd put PEX or what not into that slab for the possibility of heat even if you don't plan on wanting it. Doesn't cost much & pretty much impossible to install after the fact. Radiant in floor heating is by far the superior heading system for a shop.

 

[Dragfluid]

Good Lord. Put a 200 amp panel in there and get on with life!
Home FreakShow has a GE, 32 space, with the main breaker, for $85. Then when you want to expand, you've got the room. The breakers are under $6. They work good.

 

[Slowgsr]

Please don't install a GE panel.

 

[Nhrafan26]

Whats the HP rating on the compressor?

And if u havent poured the slab yet make sure u do a UFER ground.

Explain the ground please?
The compressor is an IR 5hp 80 gallon unit. 220V

 

[Nhrafan26]

Will more than 1 person be working at a time? Really how many tools can you operate at once if it's just you? Worst case scenario I can figure for my or many other shops is compressor, plasma cutter, lights, stereo, fridge & possibly a fan for the heater (assuming wood or gas heat not electric). Game changes a bit more if you have multiple people working.

50@ service worked for my shop (Miller Maxtar 200 welder, 30@ plasma cutter + 5hp compressor, etc.) & I never blew a breaker, well at least a main breaker. I did just upgrade to 125@ service as I put in new conduit out to the barn/shop as part of a photovoltaic system install. Solar guys pulled the extra wire through the conduit for just the price of the copper & the breaker box.

Some pretty jenky stuff in my shop from the previous owner, most notably a 150@ breaker at the house "protecting" wire rated to only 50@ (there was a 50@ breaker out at the barn/shop though providing some protection).

I'd put PEX or what not into that slab for the possibility of heat even if you don't plan on wanting it. Doesn't cost much & pretty much impossible to install after the fact. Radiant in floor heating is by far the superior heading system for a shop.

This sounds about right for usage. Most friends need direction or are by me helping so not much other going on like that.
Most is welding, compressor, lights, stereo, fan on oil burner or exhaust fan, and maybe a friend with a grinder or drill.

I want to put pex in the slab but I fear I do not have enough room under for that, the insulation and 6"of stone. I had them build the building as high on the posts as they would but still leaves me with little room. There's already about 40 ton of stone in there so digging further isn't really an option, especially considering it's all pretty much clay soil underneath.

 

[Nhrafan26]

Please don't install a GE panel.

I was looking at either a square d hom or qo panel.
I'm leaning toward the hom of course because I have a ton of breakers from changing out my house panel a while ago. (Not this location) and because it's cheaper.

 

[wyliesdiesels]

Explain the ground please?
The compressor is an IR 5hp 80 gallon unit. 220V

Its grounding done through the rebar in the footing.

What kind of slab are u pouring?

The compressor will need to be hardwired unless u can find a plug rated for 5HP or more.

U will need #10 THHN or #8/2 NM-b/Romex to wire it.

Also, a disconnect is required if farther than 50' and not within sight of the panel.

I was looking at either a square d hom or qo panel.
I'm leaning toward the hom of course because I have a ton of breakers from changing out my house panel a while ago. (Not this location) and because it's cheaper.

Go with the Q0, its copper bussed.

The homeline breakers wont fit in Q0.

 

[Pwrgeek]

One thing to consider is number of spaces. My shop (similar size to yours) came out with a max reasonable load calc of about 60A (compressor + welder + AC ). I doubled that to be safe and ran a 125A feeder from my main panel. At the shop end I went with a 200A panel not for load but because I needed 40 spaces to get things broken up the way I wanted. I may only use one or two tools at a time but I want them both plugged in at the same place so every outlet circuit gets doubled. I wanted separate circuits for each string of lights so one tripped breaker wouldn't leave me trying to get to the box in the dark. You see how this stuff can add up quick. I've got 32 circuits already planned (doing the install over the next few months as I have time) and I haven't even started using the building yet. You can bet when I do I'll realize some stuff I didn't think of up front. Moral of the story put in a bigger panel than you think you'll need the delta in cost isn't that much. As for HOM vs QO I don't get that hung up on copper buss bar, the guts of the breakers are the same and HOM is a lot cheaper but it's your money.


Sent from my iPhone using Tapatalk

 

[checkthisout]

Mobile Home Heater =20,000 watts = 100 amps.

Go with a 200 amp panel.

 

[rsnip988]

Good Lord. Put a 200 amp panel in there and get on with life!
Home FreakShow has a GE, 32 space, with the main breaker, for $85. Then when you want to expand, you've got the room. The breakers are under $6. They work good.

I got the SquareD Homeline 200A 30 space/60 circuit panel for $73 looks good and installed easily... I'm not sure why people on here hate on them other than they're inexpensive...

Mobile Home Heater =20,000 watts = 100 amps.

Go with a 200 amp panel.

I agree, with the 200A Go big and don't be sorry later

 

[Nhrafan26]

Its grounding done through the rebar in the footing.

What kind of slab are u pouring?

The compressor will need to be hardwired unless u can find a plug rated for 5HP or more.

U will need #10 THHN or #8/2 NM-b/Romex to wire it.

Also, a disconnect is required if farther than 50' and not within sight of the panel.

The slab will be just a normal slab poured inside the pole building. Under the office section it will be 4" and in both bays it will 6".

Right now I have the compressor on a 50A circuit with a plug so I can switch between that and the compressor. That's in my current house garage but I will be removing that as I wire this shop and using that stuff. I like having the big plug like that because my generator has the same plug on it so I can quickly and easily make up a mobile welding outfit.

Didn't know about the disconnect but it will have one anyway because it will be across the shop and in it's own compressor room with a homemade dryer set up.

 

[Nhrafan26]

One thing to consider is number of spaces. My shop (similar size to yours) came out with a max reasonable load calc of about 60A (compressor + welder + AC ). I doubled that to be safe and ran a 125A feeder from my main panel. At the shop end I went with a 200A panel not for load but because I needed 40 spaces to get things broken up the way I wanted. I may only use one or two tools at a time but I want them both plugged in at the same place so every outlet circuit gets doubled. I wanted separate circuits for each string of lights so one tripped breaker wouldn't leave me trying to get to the box in the dark. You see how this stuff can add up quick. I've got 32 circuits already planned (doing the install over the next few months as I have time) and I haven't even started using the building yet. You can bet when I do I'll realize some stuff I didn't think of up front. Moral of the story put in a bigger panel than you think you'll need the delta in cost isn't that much. As for HOM vs QO I don't get that hung up on copper buss bar, the guts of the breakers are the same and HOM is a lot cheaper but it's your money.

I've already been mapping out my circuits and figure on a minimum of 27 spaces so I'm either going with the 32 or the 40 space panel. I know it looks like overkill but as you continue setting up the shop and adding things you **** up the spaces quick. I ran into the same thing and ended up putting in a 40 space panel in my house a couple years ago.
I've planned on having 3 strings of lights each on their own circuit for the same reason you mentioned and also if I want to change one of the lighting circuits i still have 2 strings on to work with lighting.
I'm trying not to get caught up in the QO panel, the only thing I'm thinking is in my house it wasn't an issue, but in the shop it's going to see more heat changes, more humidity changes, dirt, dust and a harsher environment, that's the only reason I was even considering the QO panel over the HOM.

 

[Nhrafan26]

Its grounding done through the rebar in the footing.

To expand on this can someone explain what exactly this does and what is beneficial about it as opposed to not doing this and driving traditional ground rods?
The slab will be a poured slab, over approx. 6" of 2B stone, compacted, vapor barrier down with possible insulation and pex. I will also be putting rebar in at least the 2 garage bays with wire mesh under the office area depending on cost difference.

 

[nadogail]

UFER Grounds, a 20 foot piece of 3/8" rebar encased in concrete, and typically in your footing are IMHO cleaner, cheaper, neater, and just all around superior to ground rods.

Google it.

 

[lakeroadster]

To expand on this can someone explain what exactly this does and what is beneficial about it as opposed to not doing this and driving traditional ground rods?

UFER Grounds, a 20 foot piece of 3/8" rebar encased in concrete, and typically in your footing are IMHO cleaner, cheaper, neater, and just all around superior to ground rods.

Google it.

Unless you you live in an area with extremely dry soil conditions the Ufer grounding, via re-bar in the concrete, simply isn't needed. The 2 copper ground rod method works fine.

https://en.wikipedia.org/wiki/Ufer_ground

The building inspector here suggested an Ufer ground. I researched it. What I found was it may perhaps be superior for grounding, however the Ufer grounding methods isn't without it's own issues.

A disadvantage of Ufer grounds is that the moisture in the concrete can flash into steam during a lightning strike or similar high energy fault condition. This can crack the surrounding concrete and damage the building foundation

 

[Nhrafan26]

UFER Grounds, a 20 foot piece of 3/8" rebar encased in concrete, and typically in your footing are IMHO cleaner, cheaper, neater, and just all around superior to ground rods.

Google it.

I did Google it and hence my question.... is there any advantage of it?
So if i'm understanding what I'm reading about it, it is just a piece of at least 1/2" rebar OR #4 Copper ENCASED in concrete?? What purpose does this serve? I could be way wrong but I would see concrete as an insulator and not a conductor?
Is that totally wrong? They say a slab in direct contact with the earth, well mine is not going to be directly in contact with the earth, it will be over a lot of stone and vapor barrier as well as wood and insulators around the perimeter.
So I'm thinking, million dollar question....can I use one on my set up and should I?

 

[wyliesdiesels]

UFER grounds are superior to other types of electrodes and are required.

However, u cant use one because of the way your slab is being done so disregard.

 

[Nhrafan26]

Got it, Thank you.
So am I back to the "old" driving 2 separate rods in the ground 6' apart from each other and connecting everything?

 

[wyliesdiesels]

Yes!

 

[simpler=better]

100 amp panel should be more than enough for a garage, unless your running a business out of it. I ran my conduit under the slab, if you haven't already poured it something to consider. Great time saver. Use conduit that is bigger then you actually need.

So how big of a garage is this?

x2 what he said. It's cheap to throw 1" EMT down there now.

 

[Fallon]

I'd go with 1.5" and a 3/4" or 1". Minimal price difference & a lot more flexibility. The 3/4" going out to my barn will have Ethernet & phone in it shortly (by code that low voltage stuff can't be in a power conduit, so run more than 1). Although it's easy to pull a pile of wires at once, it's not nearly as easy to pull some wires & then pull more wires later.