Re-wiring my shop

[akpingel]

Hello all. I have been lurking here for a while reading as many of these threads as I can; great information. My wife and I just bought a home built in 1975, and with it a 1500 ft shop. At the moment the shop contains a 25 amp sub panel that I believe is inadequate for what I want to do. I need to be able to function out of there to work through the home improvements we need to do, so a power upgrade is at the top of the list. I am wondering what your thoughts on proceeding as such:

1. Install new 100amp panel in the shop, including the appropriate feeder line, breakers, etc. Old panel would still in use during this time. I would install the new panel relatively close the the existing.
2. Disconnect the old panel breaker in the main panel. Upgrade the breaker in the main panel to 100amp breaker (is the correct size breaker for 100amp subpanel?) and finish wiring new shop panel. Restore power to the shop.


From there I would follow similar process for the house panel which needs upgrading as well, although not in parallel as done with the shop.

Anyone see any issues with this? Do you think I need to upgrade my main panel as well? Here is a picture of main panel:

IMG_20170223_115445 by Alex Pingel, on Flickr


Thanks for the help!

Alex

 

[Rounder]

25 amp 240, is two legs of 25 amp 120. Its not bad to start with. If you get welder or bigger air compressor bigger would be better.

You can put in a 100 amp subpanel, and feed it with 50 amp breaker. 100 amp panel in garage is more then most people have. Unless you got plans 1500sq shop is pretty big so maybe you do. It is like having another house.


I think you need to update your house before worrying about it.

Put 100 amp panel in garage. I would feed new panel in garage from old, and move circuits over to new panel. Then when the time comes remove old breaker at house and hook up new cable. Isolate grounds from neutral in subpanel.




What do you have in the house? Did they put in a panel on the outside and then have the main house panel as a sub off it? I suppose no reason why not. probably was a reason at the time.

All your big loads are off the panel in the pic. So no real reason to re do, depending on what it is going on inside.

 

[Norcal]

With the deadfront being in place there is not much to tell other then it being a Murray/ Crouse-/Hinds* panel that the original installer used the 6 disconnect rule to avoid having a main breaker.

*They were listed to use ITE or Westinghouse breakers too, but neither brand name is in use anymore.

 

[wyliesdiesels]

What loads do u plan on having in the garage?

What size service do u currently have? U may not be able to tell since there is no main disconnect. Would need to pull deadfront.

 

[akpingel]

Thanks for the responses thus far. I didn't specify but yes it is a Murray panel. The house panel is also a Murray, and it is completely full with 3 twin breakers already in it. It is 100amp, total service is 200 amp (according to recent home inspector). I would like to redo this panel after I get the experience doing the shop panel so I can hopefully do it a little quicker and without incident.

Plans for the shop include
Assume this is a one person shop... buddies will be over but I cant imagine one person welding while another is operating a table saw.
240V 60 gal air compressor ~16 amps
240V dust collector ~ 10 amps
240V table saw ~14 amps
Welder, do not currently own one so not sure of the draw, but wouldnt run dust collection when welding.
lights on ~10 amps (?)
TV or receiver on for tunes in the background..

no immediate plans for major heat or ac right now, but I do have a smaller elect heater and window unit. Possibly running multiple fans in the summer.
Plus all other tools, etc.

Thanks,
Alex

 

[matt_i]

I would try, if you have a basement, or access behind that wall that isnt restricted, to put that panel inside...

Anyway, I'd try for a 90A feeder to a typical 100A residential panel you get at the box stores, for your shop. I've always used Square D QO and Homeline but I feel certain the other manufacturers aer just fine. Then you have what you need plus some room to grow.

 

[akpingel]

Good to know. I have a crawlspace but I dont think I have enough clearance where the panel is. I will have to look around and see what options there are.

Here is a picture with the deadfront off.
IMG_20170306_181510 by Alex Pingel, on Flickr

Alex

 

[wyliesdiesels]

Looks like 4/0 AL...

Post a pic of the meter.

Is the service overhead or underground?

 

[Norcal]

Hard to see but it looks like a offset ****** entering the panel at the lower right. See the photo in post #1, it looks like a easy panel swap if no upgrade is required.

 

[wyliesdiesels]

Hard to see but it looks like a offset ****** entering the panel at the lower right. See the photo in post #1, it looks like a easy panel swap if no upgrade is required.

Good catch.

I thought i saw a ****** but hard to tell on a 5" screen.

 

[akpingel]

Service is underground. The line on the left is the current line to the shop. The shop is about 15 feet straight across from the meter. I am assuming I will have to go out of the botton left side with larger conduit and plug the bottom left knockout. Other pictures:
Meter by Alex Pingel, on Flickr
Meter by Alex Pingel, on Flickr

 

[AntonLargiader]

What size is that conduit running to the garage, and would you like to re-use it? For instance, if it's 3/4" you can pull 60A service to it without any digging. But that looks bigger than 3/4".

 

[akpingel]

I was thinking about this again and how to do it safely. There is no main breaker to shut off the main panel, so when it comes to wiring the new subpanel on the main panel, I would have to call the poco to get power shut off, correct? If I am going to do that, should I go ahead and invest in a new main panel that would have a master breaker so when I do the house subpanel I do not have to call the poco?

Thanks,
Alex

 

[Contract_Pilot]

I am installing a 100A Sub Isolating the Garage On Load Center. akpingel, You will see my main load center has no main breaker simple to do while it is hot no need to get power shut down to ad a sub.

 

[Stuff]

Is the inside panel fed by a 3 or 4 wire cable? With the pipe full it might be the hardest part to replace.

Since the garage feed is UF, is the PVC portion just at the box for protection? Most likely you will be digging for the new cable.

 

[fowldarr]

Good catch.

I thought i saw a ****** but hard to tell on a 5" screen.

Out of context, this is my favorite forum post ever. I would like to weigh in on the electrical, but it is really not my strong suit. In fact, my policy on electrical is that if I have this many questions it is best to hire a professional (before I electrocute myself or cause a fire). Good luck. Have fun. And be safe.

 

[akpingel]

Is the inside panel fed by a 3 or 4 wire cable? With the pipe full it might be the hardest part to replace.

Since the garage feed is UF, is the PVC portion just at the box for protection? Most likely you will be digging for the new cable.

I will have to check on the inside panel. However I plan on digging a trench and running 2" conduit, carrying 1/0,1/0,1/0,2 alum URD the ~50' to the new panel. I want to also go ahead and run a line for NG and a line for water while I am digging. Not sure why they used the white PVC, but it is also at the shop's end... Do I have the right wire?

Thanks,
Alex

 

[James-W]

Would you consider having a separate electrical service to the garage? When I built my garage I had the power company install a new 200 amp electrical service.

I have a 100 amp service to my house. If I were to run a sub-panel from the house to the garage I would first need to upgrade my house electrical service. Instead of doing that, I had the power company just run a new 200 amp service from the street to the garage. They did it for free so I figured I may as well get a 200 amp service instead of a 100 amp service. I seriously doubt I will ever need 200 amps, but I have it available in the event that I do need it. Yes, there is a monthly meter charge of $10 but when I considered the cost of the alternative method of getting power to the garage, I much prefer this way of doing it.

Besides all that, I have never heard of anyone saying they were sorry they have more power in their garage/shop than they need, it's always the other way around, sorry they don't have more power available.

That's my two cents worth, you may want to consider it, or not, as with anything else, it's entirely up to you.

 

[wyliesdiesels]

I was thinking about this again and how to do it safely. There is no main breaker to shut off the main panel, so when it comes to wiring the new subpanel on the main panel, I would have to call the poco to get power shut off, correct? If I am going to do that, should I go ahead and invest in a new main panel that would have a master breaker so when I do the house subpanel I do not have to call the poco?

Thanks,
Alex

If youre careful u dont need to shut off the power.

Out of context, this is my favorite forum post ever. I would like to weigh in on the electrical, but it is really not my strong suit. In fact, my policy on electrical is that if I have this many questions it is best to hire a professional (before I electrocute myself or cause a fire). Good luck. Have fun. And be safe.

Why may i ask?

I will have to check on the inside panel. However I plan on digging a trench and running 2" conduit, carrying 1/0,1/0,1/0,2 alum URD the ~50' to the new panel. I want to also go ahead and run a line for NG and a line for water while I am digging. Not sure why they used the white PVC, but it is also at the shop's end... Do I have the right wire?

Thanks,
Alex

URD cannot be ran inside.

U would have to transition to another cable type on the outside.

1/0 AL is overkill for 100a feeder at 50'.

U need min. #1 AL...

 

[LX-Markham]

Out of context, this is my favorite forum post ever

Why may i ask?

Did you re-read it?

I thought i saw a ****** but hard to tell on a 5" screen.

 

[akpingel]

URD cannot be ran inside.

U would have to transition to another cable type on the outside.

1/0 AL is overkill for 100a feeder at 50'.

U need min. #1 AL...

I thought you could use URD inside to the panel if it was inclosed in conduit up to the subpanel? The subpanel will be directly inside (plus vertical distance) of the feeder.

Thanks,
Alex

 

[pattenp]

I thought you could use URD inside to the panel if it was inclosed in conduit up to the subpanel? The subpanel will be directly inside (plus vertical distance) of the feeder.

Thanks,
Alex

Your AHJ may allow it, but the NEC says USE only rated wire is not to enter the structure.

See NEC 338.12(B)(1)&(2). Typically URD is only USE rated, but the ratings should be checked on the cable insulation.



*

 

[akpingel]

Your AHJ may allow it, but the NEC says USE only rated wire is not to enter the structure.

Thanks. I was hoping for a less complicated install. That makes sense. Back to the drawing board!

Sent from my Pixel using Tapatalk

 

[pattenp]

Thanks. I was hoping for a less complicated install. That makes sense. Back to the drawing board!

Sent from my Pixel using Tapatalk

There are other wire types to use that can go inside. Individual RHH/RHW/USE or MHF are direct bury and can go inside the structure when in conduit. You need to make up the cable if using individual RHH/RHW/USE wire, unlike URD or MHF which come ready made in 4 conductors. Or use individual wires of XHHW in conduit the whole run.

Edit: I went back and looking at your post if doing conduit the whole run I'd use the aluminum XHHW using three #1 and one #6 for 100A if the distance is less than 100'.

 

[fowldarr]

If youre careful u dont need to shut off the power.



Why may i ask?





U need min. #1 AL...

Because it can be hard to see ******* on a 5" screen.




Sent from my iPhone using Tapatalk

 

[wyliesdiesels]

I thought you could use URD inside to the panel if it was inclosed in conduit up to the subpanel? The subpanel will be directly inside (plus vertical distance) of the feeder.

Thanks,
Alex

Thats according to the urban legend code book...

Ive always been baffled by this misnomer.

U need to realize that conduit doesnt change the non fire resistant rating on the insulation.

 

[wyliesdiesels]

Because it can be hard to see ******* on a 5" screen.




Sent from my iPhone using Tapatalk

Lol yeah i get it now.

I was half awake last time so i wasnt paying attention.

 

[akpingel]

Ive been making progress on this project. It took me several weekends to dig out the trench needed to bury the line 24". The gravel driveway was full of filler including bricks, asphalt and field stones. When it wasnt filler, it was solid North Carolina clay. Anyway that is done now it is time to complete the conduit and pull through the wire. I am also going to re-balance the main breaker panel by moving the dryer to the left side and installing the new shop breaker on the right.

For anyone curious what the white conduit was all about, it was this. The gray conduit was just sitting in the open white conduit.

Hmm by Alex Pingel, on Flickr

Nothing glued up by Alex Pingel, on Flickr

 

[akpingel]

Edit: I went back and looking at your post if doing conduit the whole run I'd use the aluminum XHHW using three #1 and one #6 for 100A if the distance is less than 100'.

I should add I took this advice and will pull 1/1/1/6 through 1.5" conduit. Thanks for the help pattenp.

 

[sstec]

just for Wylie. . .. . . . . .

 

[wyliesdiesels]

Lmao

 

[akpingel]

I have two questions about my new panel install.
#1 I have the panel mounted between two studs plus mounted to 5/8th OSB, also mounted to the studs. Essentially it is a recessed install offset the thickness so that it will be flush when I install the wall covering. I believe code is that the panel should be mounted to something at least 3/4" thick, but does it matter since I have it mounted the panel to the studs as well?

#2 I moved the fireblock up to about 11 inches from the top of the panel. Will this location be OK? Should it be closer or further away from the panel? Also I plan to insulate the walls before closing them back up, so is fireblocking a moot point?

Sorry I thought I took a picture but didnt, but I can get one tonight if needed.

Thanks,
Alex

 

[akpingel]

Here is a picture

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[Norcal]

The panel between the studs is fine, I like a block about 12" OC from the top to staple the cables before entering the panel

You chose a "Zinsco II" panel, always has to be a manufacturer at the bottom & Eaton BR is it. I prefer to use the same make as existing equipment unless obsolete, nothing like a hodge podge of equipment to clutter things up, but if existing was a Bryant/Westinghouse/Cutler-Hammer/Eaton BR then I grit my teeth & use it, Murray* is still around so that what I would have chosen, but that ship has already sailed.

*Murray was also formerly known as Crouse-Hinds.

 

[akpingel]

You chose a "Zinsco II" panel, always has to be a manufacturer at the bottom & Eaton BR is it.

Yep that would be my luck, because I agree so far I do not like this thing. The knockout in the bottom middle fell out at a size too big for what I need. The breakers seem flimsy when installed, and there really is only one configuration for the BR ground bar and neutral when setting it up as a subpanel... all of the holes pre-drilled but for what bars? I impulse bought this on-sale and I should have done more research.

 

[akpingel]

Thanks for all of the help. I was finally able to get this project done this past weekend.


Alex

 

[casmurbax]

May we see a picture(s) of the completed work?

Looks good from what you posted.

 

[shaggyant]

Thats according to the urban legend code book...

Ive always been baffled by this misnomer.

U need to realize that conduit doesnt change the non fire resistant rating on the insulation.

I must be confused here. The panel I saw in the OP's post is mounted outside. What's the problem with running URD here?

The reason I ask is that I am planning on running URD from my external double logged meter to my garage panel and running up the wall outside both the house and shop. Is this not ok? The only place the URD will be inside the building is the couple of inches where it is inside the garage main panel.

 

[Norcal]

It's still inside the building so a no go.

 

[pattenp]

The wording in the NEC says USE only rated wire is to be terminated on the outside of the structure. Terminated in an outside panel is okay.