Electrical upgrade to shop (or to house, or to house and shop.....)

[Carl Beckett]

Thanks for the comments.

So if I run 200A to the shop, I can also drop a 200A run to the house off it? (if so then yes, I will spring for the extra $$ now)

Sorry Thomas - what I mean by a separate circuit wasnt a single circuit for everything - just that I want to be able to 'kill' all the big rotary equipment when Im not in there, in case some wondering child decides to punch a button for no reason (kids are not allowed in my shop without me, but just the same I dont mind having it shut down. But I still want lights/110. And there will be multiple circuits/breakers for this.

What are everyones thoughts on GFI breakers? Should I plan for those?

The biggest thing I have is a 15 hp belt sander (three phase, which I plan on running with a static phase inverter... I know, not ideal), combined with a 5hp dust collector, 1.5ton heat pump, and lights all at the same time. Then worst case I do this when my wife is baking cookies, drying clothes, and running two central AC units at the same time..... (Im surprised at times that the existing 100A service does all that... but I think its a timing thing, where not all running at once has happened. Yet.) And I keep adding stuff (like the shop heat pump is an up and coming add on). A welder would be nice..... a nice Tig inert gas... but I digress....

For inrush current - a higher service in the shop gives me a little more margin than I would get with the 60A.

[Carl Beckett]

OK - but here is the thing with the 200A all the way to the house:

200A, 240 single phase - at 250ft gives a 3.1% voltage drop with 3/0 copper and 3.5% drop with 4/0 Aluminum. So not quite below the 3% desired threshold.

If I go 150A at the house - 250 ft - I get 2.9% voltage drop with 2/0 copper and 3.3% with 3/0 Aluminum (going to 4/0 Al is 2.7% drop)

Ah - but I guess I can have larger wire between the street and shop. For that service its 1.6% drop with 2/0 Cu, and 2% with 1/0 Cu.

Dang it - Im going to have to calculate two resistances in series to get this sized - its an expensive answer (this wire is expensive these days, especially copper!). And the thought of pulling a bunch of 4/0 Al wire sounds like a pain.

[John Lanciani]

If it were me I'd use 350-4/0 (2 hot legs are 350mcm, neutral is 4/0) Al from the street to the shop and 4/0 Al to the house. I'm pretty sure that you will need 4 conductors between the shop and house, but my code book is not in front of me right this second. Probably looking at 3" sch40 pvc for both runs.

[Thomas Bank]

So if I run 200A to the shop, I can also drop a 200A run to the house off it? (if so then yes, I will spring for the extra $$ now)

The only problem that you might run into is whether the wire size for 200A will fit into the lugs for the 100A main on the panel. But there are ways to make that work too. There is really nothing in the code stopping you from oversizing wire.

Sorry Thomas - what I mean by a separate circuit wasnt a single circuit for everything

Ok, just wanted to make sure. Sounds like you've got the right plan.

What are everyones thoughts on GFI breakers? Should I plan for those?

You can see the GFI breakers in my panel - they're the ones with the extra yellow button on them (4 of them). They serve the 110V outlet circuits on the first floor. With a concrete floor and being on ground level in the garage, GFI is required. You'll probably get a lot of people saying to just put a GFI receptacle in the first box on the circuit. That is allowed. But my reasoning was that with four circuits and the possibility of things blocking outlets, I have all the GFI breakers in one place and know where to go to reset them. Otherwise it could be "well, this circuit is the one that starts with the outlet behind the air compressor - let me move some things to get back there and reset it..." Or, worse, if my father (or someone else) is over there and trips one and I have to explain to him over the phone where to go to reset it. The breakers are more expensive than the receptacles, but the difference between four GFI breakers and four GFI receptacles in the grand scheme was pretty small - and, to me, worth the aggravation of figuring out which outlet I had to get to in order to reset it.

On a tangent, a woman I was dating a number of years ago tripped the GFI in her bathroom. Except that the outlet in the bathroom wasn't a GFI. Nor was any outlet she could find. And the breaker wasn't a GFI and wasn't tripped. So I got the call to come help and went over to see what I could come up with. Looked in the bathroom, out in the hall, the other bathroom upstairs bathroom, the downstairs bathroom, literally everywhere. Confirmed that the breaker wasn't a GFI and wasn't tripped. Standing there in the basement, looking at the electrical panel, I was just scratching my head when I noticed a GFI receptacle below the panel... Pushed the button on it and it reset. Yep, that was the GFI for all the bathrooms in the entire house! The electrician ran from the breaker, out of the panel to the GFI receptacle, and then up through to every outlet in three bathrooms... To me, the extra expense of wiring a GFI into each bathroom so you didn't have to run all the way down to the basement would have been more than worth the cost.

[Richard Jones]

.......... I'm pretty sure that you will need 4 conductors between the shop and house............., .

Correct.

OK, inspector hat on. I'm the Building Official for my jurisdiction. If a homeowner comes in and wants to do his own wiring, I'll try to help, depending. If he doesn't know 12-2 from apple butter, I will recommend that he get an electrician to "help" him. I will be as helpful as the law will allow, but I won''t design it.

To those inspectors spoken of in this thread that merely inspect, shame on you. Part of your job is customer service and education. I have an open door policy. Also, my ego stays at home when I leave for work..........

We're not all asshats...........

[Carl Beckett]

Correct.

OK, inspector hat on. I'm the Building Official for my jurisdiction. If a homeowner comes in and wants to do his own wiring, I'll try to help, depending. If he doesn't know 12-2 from apple butter, I will recommend that he get an electrician to "help" him. I will be as helpful as the law will allow, but I won''t design it.

To those inspectors spoken of in this thread that merely inspect, shame on you. Part of your job is customer service and education. I have an open door policy. Also, my ego stays at home when I leave for work..........

We're not all asshats...........

Hi Richard,

To be clear - I have usually had great experiences making an introduction and discussing a project up front with an inspector (have lived in a number of states and have had good experiences). It seems (to me at least) that they each have certain elements they take particular attention to - which can sometimes be a style difference. Fine by me - Im there to learn what they deem important, to make it go smoothly, and do a good job.

Where I live now is a little more difficult. But no worries - just need to go do my homework, and do a good job. And there is a fair bit to this job - part of discussing with a contractor even, is to know the options and tradeoffs myself - which will make me a better informed customer (some contractors like this, some dont). A lot of this (not all) I can do myself and save some $ (if done properly).

You sound like an inspector I would get along well with - it really is about education and learning (and some things just are over my head to attempt - which doesnt mean I dont want to learn about them). A service line is definitely a new one for me - so thanks to everyone for sharing the knowledge - it helps!

[Steve Meliza]

I agree with Thomas on the GFCI circuits. When I was doing my electrical project in the garage I had 6 circuits needing GFCI and decided to put in two as breakers to give them a try despite being told by a licensed electrician (my father) that he would use GFCI outlets because they are cheaper, even if you had to replace them a couple times.

The problem comes in not just when needing to locate and reset a GFCI, but also in performing the monthly testing, or any testing at all. Two of the GFCI outlets in the garage (lights and garage door opener) require a ladder to reach them. The other two GFCI outlets are on the walls, but one is hidden behind the air compressor and requires me to lean over the top and unplug it to get access to the test and reset buttons. The other outlet has the table saw stored in front of it so testing requires a one legged ballet movement to reach. But to test and reset the GFCI breakers I have simply to open the breaker panel, punch the yellow buttons, then reset the breaker. However, I would be remiss to not mention that the breaker for the air compressor was bad and kept tripping so replacing it cost about $3. In summary, the outlets will be cheaper but the breakers a lot easier to use.

[Thomas Bank]

Two of the GFCI outlets in the garage (lights and garage door opener) require a ladder to reach them.

Actually, you shouldn't need GFI protection on dedicated outlets - particularly ones not at "ground level." I wasn't required to have a GFI on the circuit for my garage door openers.

[Richard Jones]

Actually, you shouldn't need GFI protection on dedicated outlets - particularly ones not at "ground level." I wasn't required to have a GFI on the circuit for my garage door openers.

Thomas,

NEC 2008 now says ALL, no more exceptions. I'm not sure why the garage door receptacle needs to be GFCI, but there it is.............

[Jim Andrew]

Wish more inspectors were like Richard Jones.

[Steve Meliza]

NEC 2008 now says ALL, no more exceptions. I'm not sure why the garage door receptacle needs to be GFCI, but there it is.............

Yep, and I had to follow 2011 NEC. The only exception was a single outlet on a dedicated circuit to power a fridge and even that might be an exception specific to Oregon. You never know what the next guy is going to do, maybe use an outlet on the garage door opener circuit to power Christmas lights or cut open a hole in the roof for a new vent in a rain storm.

[Thomas Bank]

NEC 2008 now says ALL, no more exceptions.

Thank you for the update. I hadn't caught that one.

[Greg Portland]

Option 1)
I could go ahead and drop a 60A off this - and run 60 to the shop. Approx 150ft between the house and the shop. If I go this route Im putting conduit in sufficient to upgrade the service at a future point in time.

Option 2)

I could just suck it up and upgrade everything. I could go 200A to the house, then a 100A subpanel back out to the shop. This means a lot of wiring and panel reworks. Given it would be too much for me to do all at once it would mean hiring labor and sounds $$$$$

Option 3)
I could route a 200A to the shop, then drop the house off this. I could go ahead and leave the house 'as-is' (leave the current 100A service and panel). but I could pull larger wire between the shop and house. Then some future point I could upgrade the load panel. This way I can do all the wiring and have it 'ready' - then its a matter of swapping both ends of current service to the new wiring, and done. This would be a quick switch and then I have both the house and the shop to work on with being able to shut it down.

What's the current subpanel for (looks like random things around the house)? I was in a similar position and replaced everything. I'd run the new service (as big as you can get) through conduit to a new combined panel. Run a line to your shop sub panel from the house. As mentioned before, multiple meters can equal commercial billing rates. I've seen the powerco say otherwise and then bill commercial (at that point you're stuck).

I did all the work myself except connecting the main service to the panel. My local power co. required a licensed electrician to do that while they are there to shut off the power @ the street.

[Jim Neeley]

Yep, and I had to follow 2011 NEC. The only exception was a single outlet on a dedicated circuit to power a fridge and even that might be an exception specific to Oregon. You never know what the next guy is going to do, maybe use an outlet on the garage door opener circuit to power Christmas lights or cut open a hole in the roof for a new vent in a rain storm.

It must be Oregon-specific. Both 5the 2008 & 20011 NEC, in Exhibit 210.10, show examples of garage locations requiring GFCI. The examples they give are wall receptacles, work benches, freezer and garage door opener (and its receptacle is on the roof).

One important factoid for readers here is that individual states choose whether or not to adopt the latest code, or whether to adopt the code at all at the state level.

According to Mike Holt's site: Alabama, Arizona, Hawaii, Illinois, Kansas, Maryland, Mississippi, Missouri and Nevada have chosen not to adopt it at the State level, leaving it to local jurisdictions to make such choices. Of the rest of the states, Conneticut and District of Columbia are operating under the 2005 code with the balance approximately evenly split between the 2008 and 2011 versions.

The 2005 NEC provided for the exception for a receptacle for a freezer in a garage and for receptacles "not normally accessible". These exclusions disappeared in the 2008 code.

Given the reality that any state can change at any time makes it difficult to give other than the most conservative of advice here, with lots of caveats.

Just my $0.02.. YMMV.

Jim

[Chris Friesen]

Have you done a load analysis? When I looked at mine things looked a bit iffy for running 60A out to the shop with only 100A on the house panel. Where's your existing panel? If you've got room you might consider a new 200A panel right beside the existing panel, then feed the existing panel from it. Minimal disruption in the house that way, and you only need to run 60A feeders between the house and shop. Alternately I'd look at your option 3, though this does mean you need 100A feeders between the shop and house, and likely new ground rods at the shop.