Sub-panel installation and wiring

[Anonymous]

Posted by: MitchShatto (old forum transfer)
Posted: 25 Aug 2002 10:38 am

Based on the linked diagram...

http://webpages.charter.net/mshatto/Elec_Layout.gif

I am interested in installing a sub-panel in my basement. Specifically, I would like it placed in a utility room, denoted by the black box where all of the colored circuits terminate. My Main box is my garage and it was recommended that I pull 6 AWG from a 50 Amp breaker in the Main breaker of the garage to a sub-panel in the basement.

I'm pretty comfortable with this, however, I'm not certain about the 6 AWG cable...? Can I run it inside of the I-beam that runs from the garage side of the house to the sub-panel utility room? Also, will I be required to install conduit behind the wall and floor to extend this 50 amp circuit to the ceiling of my basement?

Thanks in advance.

Mitch

[Anonymous]

Posted by: Wgoodrich
Posted: 25 Aug 2002 11:49 am

YOU SAID;
I am interested in installing a sub-panel in my basement. Specifically, I would like it placed in a utility room, denoted by the black box where all of the colored circuits terminate. My Main box is my garage and it was recommended that I pull 6 AWG from a 50 Amp breaker in the Main breaker of the garage to a sub-panel in the basement.

REPLY;
6 awg is allowed to be protected by a 60 amp breaker if you like. 50 or 60 amp breaker protecting this 6 awg copper feeder is allowed by the NEC either way is fine. Big thing is this 6 awg feeder must have a black, red, white and a bare or green conductor in that cable. Sub panels are not allowed to be served with 220 volts to a subpanel unless a four wire cable including an equipment grounding conductor is in that same cable sheath. 6/3wGrnd Romex is fine as this feeder serving that sub panel that also must be rated no smaller than 60 amp and may even be a 100 amp rated sub panel. The size feeder and breaker protecting that feeder located in the main panel tells you how many amps can be pulled on that sub panel. Remember that you have to isolate the neutral bar from the grounding bar and metal case of the sub panel inside that sub panel. No main breaker is required in that sub panel. Absolutely do not add a new ground rod to serve that sub panel. The ground must be served by the same ground bar as the main panel through that equipment grounding conductor in that feeder serving that sub panel.

YOU SAID;
I'm pretty comfortable with this, however, I'm not certain about the 6 AWG cable...? Can I run it inside of the I-beam that runs from the garage side of the house to the sub-panel utility room? Also, will I be required to install conduit behind the wall and floor to extend this 50 amp circuit to the ceiling of my basement?

REPLY;
If you I-beam is wrapped in would you should be able to fish the Romex cable through that void along that I-beam and be fine. If you have no wood wrapping that I-beam then you will have to devise a way to support that Romex cable to that I-beam every 4 1/2 feet as required by the NEC. This supporting on an exposed I-beam may take some imagination. YOu are not supposed to drill or cut on that supporting I-beam unless an AHJ -building inspector - or an engineer provides his stamp of approval as to the technique of tampering with that I-beam concerning drilling or cutting. Otherwise you plan to follow the I-beam is fine. If the I-beam is wrapped in wood and the cable is fished then the question of supporting the cable would be mute. The NEC allows fishing in a void without the normal supporting of the cable being required.

OPINION;
I noticed that you designed you branch circuits pretty light especially the lighting. It is good to vary the branch circuits for the lighting but also remember unless a receptacle if for a dedicated specific intended use all receptacles are considered as general lighting branch circiuts allowing both receptacles and lights on the same branch circuit. If you combined the lights on with your receptacles and ran 12/2wGrnd as your branch circuits you could install 13 receptacles on a circuit and be within commercial design of loads allowed by the NEC. If you installed the same number of receptacles as you have and combine the lights evenly on those receptacle circuits you should be fine powering your wiring design in that basement on 3 - 20 amp branch circuits.

If you compared prices and labor you could fish 4 or 5 12/2wGrnd cables from the main panel to the basement circuits eliminating the sub panel and actually have more power in that basement than the 60 amp sub panel would provide. You would also be able to run those 12/2wgrnd cables all at the same time along that beam as easy or easier than one larger 6 awg cable. In other words I see no advantage of your installing a sub panel versus keeping all the breakers in the main panel and having more power for less money invested. Just my thoughts on your design. YOu seem to meet NEC requirements from what I see in your wiring diagram.

You are showing what looks like closet lights. If these are clothes closets you have clearance and light design rules you need to consider in the NEC that apply to clothes closets.

Any receptacle in the basement in nonliving or unfinished areas must be GFI protected.

You show no smoke detector in this new area. Should consider a smoke detector.

Remember that a sub panel as well as a main panel is not allowed installed in a bathroom or place of storage. Also you must maintain a dedicated wall space of 30" wide and 30" clear approach from ceiling to floor for that sub panel or main panel per the NEC rules.

HOpe this helps

Wg

[mshatto]

Sorry for the delay Wg, but I have been caught up at work. I wanted to thank you for the professional advice. I believe you are correct about the 'less power for more money' sub-panel installation, but I really want my basement separated from the first level.

I appear to have other issues that have not been tackled yet, like scary inspection rules...A few conversations with others has led me to believe that I may experience some problems. They (local inspectors) charge $270 for a 12 month permit, then you must reapply. I cannot watch this kind of money go down the tubes, so I am accomplishing as much as possible without hiding anything, so when I finally submit an application for permit, I am theoretically 'way' ahead and can possibly complete everything in 12 months. We will see. I think I need to be very careful with the inspector upon first visit.

Again, thanks.

Mitch

[Wgoodrich]

Do your research. Read everything on the subject that you can remembering that not all of what you read is 100% accurate thereby you should read as much as you can from as many different writers or forums as you can. This will give you information as to how to do your project meeting the NEC rules and seeing it written by more than one source adds validity to that written word concerning accuracy. Don't be reluctant to ask questions that you are having trouble understanding as you read what you can.

Contact your inspector on first visit. Ask such things as licensing, bonding, permit costs, proof of skills, what his or her as the AHJ believes should be considered as existing and acceptable by him or her as existing in your project. Ask about added costs to extend a permit. Generally feel him or her out to get an idea if you are lucky and have an inspector that is trying to be there to help and be a source of information, or if you are unlucky and have an inspector that may be on an ego trip telling your to do it because he or she says so, that stincks but they are out there both kinds. Good luck with what you find as an inspector, hope they are to help and not to promote self esteem or politics.

Let us know how you come out and good luck

Wg