Need Help wiring up basement shop (New load center)

  • Advertise with us

« back to Focus on the Workspace forum

Forum topic by TerryDavis posted 11-29-2013 03:48 AM 1679 views 0 times favorited 9 replies Add to Favorites Watch
View TerryDavis's profile


5 posts in 2031 days

11-29-2013 03:48 AM

To all of you expert electricians out there: I am in the process of building up a small shop in my basement. My house currently has a GE Main breaker (200a, I think). I purchased a 100a contractor kit from Menards (CLICK HERE FOR LINK TO ITEM) As I am not extremely well versed in large scale wiring like this, I thought I would consult somebody with more knowledge. What is the best way to wire up the new box? The boxes will be located side by side (about 10” apart). Do I need to install a breaker in the main box to feed the power to the new box? Or can I just come right off of the main input? Any advice would be greatly appreciated!

-- -TD

9 replies so far

View Andre's profile


1837 posts in 1806 days

#1 posted 11-29-2013 03:58 AM

Best to check with the local electrical authority, When I wired my shop I required a breaker in my main panel to supply the second panel. So if you are running a 100A service in your shop you will need a 100A breaker in main panel. Unless you direct feed from main line? You will most likely require a permit anyways.

-- Lifting one end of the plank.

View wiser1934's profile


524 posts in 3147 days

#2 posted 11-29-2013 04:23 AM

you need a breaker in your main panel to feed the subpanel. i have no idea what you are going to run off the sub panel. figure up your total amperage draw and get a breaker to cover this. also match the wire capacity to the breaker size. then break it down in to individual circuits. hope this helps.

-- wiser1934, new york

View NoLongerHere's profile


893 posts in 2676 days

#3 posted 11-29-2013 03:12 PM

a separate 100 amp panel for a basement below seems like a lot, unless it’s a huge basement and you have a huge shop. I’m wondering if you even need this? Is your existing box full? Do you have access to the conduit from the panel? How much power do you need?

You definitely need to talk to an electrician. Roughing in electrical is not that hard really. I bet you could get your electrical buddy to help lay it out for you. He may even be willing to help pull wire and hook up the new circuits.

Recently, a friend of mine couldn’t sell his house until he ripped out all of his “happy homeowner run amok” Romex electrical work in his basement shop because it wasn’t to code.

Down the street, a neighbor burned his garage to the ground because of his BS wiring. Idiot walked away with thousands of dollars because he claimed all the crap he had stuffed in there….. which is what started the fire!

I digress…... be safe my friend.

View crank49's profile


4030 posts in 2971 days

#4 posted 11-29-2013 04:09 PM

There are many, many issues with a person of limited knowledge on the specific subject of wiring practice installing a 100amp sub panel.

I mean absolutely no disrespect, but your suggestion of feeding off the main without a breaker gives me pause and causes great concern for your safety.
1. The mains will always be hot unless you have the power company come out and pull the meter, so there is no safe way you can attach wires going to your sub-panel to the mains.
2. The power company will not shut down a service like this for modifications and then power it back up unless there has at least been an inspection and probably a new permit issued.
3. If your main is a 200 amp service, the feed going to the sub-panel would also have to be rated at 200 amps if it was attached to the mains without a breaker.
4. It’s possible that to get a new permit for a rewired panel, all the existing wiring in the whole house would have to be brought up to current code. Could be very expensive, depending on when your house was built and what the local codes are.

View oldretiredjim's profile


206 posts in 2385 days

#5 posted 11-29-2013 04:37 PM

Agree with the comments above. First and foremost is a breaker in the main to feed the sub. And from your discussion I would recommend having an electrician install that breaker. Once the breaker is installed in the main with a feed to the sub you can work in a cold box for the rest. Many of us have probably worked hot at one time or another and have a cooked screwdriver to prove it.

Spend the money to get the first step done correctly and get a breaker for the sub. And agree with reedwood, 100 amps are a lot unless you are welding and I would not do that in a basement. Once the sub is on a breaker, the rest is easy.

View Andre's profile


1837 posts in 1806 days

#6 posted 11-29-2013 06:06 PM

The panel Terry bought is a 100amp, you can run power directly to this as it will only allow 100amps of service because of the preinstalled breaker, same as coming off main panel, you have access to 100 amps make sure it is there if you want it. For the basic basement work shop(with no 220V tools) 40amp would be the minimum I would go. Small table saw, band saw, router/shaper, drill press and some dust collection eats up a lot of breakers, plus being in the basement good lighting is a must. Main thing to remember if you do not know, find a professional get a permit and have it inspected, no permit and your insurance is void.

-- Lifting one end of the plank.

View teejk's profile


1215 posts in 2684 days

#7 posted 11-29-2013 07:55 PM

For that distance he bought the wrong panel (didn’t need the “main” in the subpanel and should have bought “lugs only”).

He will still need to come off the house panel on a GE breaker…into the main breaker on the sub panel (no other way to get juice there without doing something really really stupid). That means he has two “kill” points on the sub panel within 18” inches of each other that is a waste of money (would be prudent to kill the subpanel on the main panel rather than using the “main” on the subpanel). Probably didn’t waste too much money though because Menards sells the SqD Homeline main panel “kit” that includes a few breakers that have to be bought separately with the “lugs only” panel.

As for 100a on a sub, there is never enough room in any panel with current code requirements and the cost differential is spit. He might even have to relocate a few circuits on the existing panel to allow for the breaker to feed the sub-panel.

View Grandpa's profile


3259 posts in 2675 days

#8 posted 11-30-2013 02:14 AM

Everything going out of your old panel should be on a breaker so that takes care of the question. Install a 100 amp breaker and the proper size wiring to the sub panel. Remember that the commons and grounds cannot be on the same bus in the sub panel, only in the main panel. Remove the bonding strap in the new panel. The main breaker in the new panel is okay but not necessary since you have the panel protected and switched in the old panel. If this panel was cheaper with the main installed then no sweat. It doesn’t take up any useable space. The codes are constantly changing so the idea of having a licensed electrician install and ground the new sub panel properly would be a good idea. Running the individual circuits is pretty straight forward but the new panel needs to be properly grounded. Upgrading the entire house is not necessary unless you live in some place like California. You usually only have to upgrade when you work on that part of the electricity. If you rewire the kitchen cabinets then they have to be brought up to todays codes. There are a few places that rewire those changes to sell a home but like I said those are limited to places where it is against the law to carry a finger nail clipper on the street.

View bbc557ci's profile


595 posts in 2074 days

#9 posted 11-30-2013 02:47 AM

I’m in the process of wiring my new attached garage/shop. I ran 6/3 from a 50 amp breaker in the main panel in the basement, to the lugs of the new sub panel in the shop. I’m not an electrician. But I did the research and bought a decent how to book on electrical several years ago. I’m about 75% done as of today, after lots of head scratching…. It’s not all that difficult. Just research it and take your time. Oh….buy about twice as much wire for lighting, switches and receptacles as what you think you’ll need !! I have the ceiling lighting (flouresent) on 14/2, and everything else on 12/2. Heading to Home Depot tomorrow for another roll of 12. Hard to believe I went through a 250 foot roll and still need more.

-- Bill, central where near the "big apple"

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics