Two 20A circuits, same box 2 gang box

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Old 08-04-14, 09:03 AM
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Two 20A circuits, same box 2 gang box

First off, I'm new to the forum so be kind and let me know if I'm leaving out any pertinent information.

I am moving a spare refrigerator and a chest freezer to my basement in an unfinished section. I was planning on adding 2 20A circuits with 12/2 Romex, one for each appliance.

They are going to be right next to each other so my plan was to bring the 2 12 awg cable runs through a single piece of 3/4" or 1" PVC conduit to a 2-gang FSE box. There would be two 20A receptacles, each receiving 1 of the 20A circuits. Basically, 2 circuits sharing the same box. What is right or wrong with this plan?

Also, I would prefer not working with metal conduit and boxes, but I will if I have to. I would just need to ground the outlet to the conduit and then ground the conduit to a nearby copper pipe, right?

A couple side questions:

1) Because this is in an unfinished basement and the appliances will not be moved (ever), can I get by without using a GFI outlet?

2) Ground is always an important consideration, so since I am planning on running through plastic and each circuit will be a direct run back to the breaker box can I just ground off the bus bar in the breaker box?

Thanks in advance for any insight you can give.
 
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Old 08-04-14, 09:35 AM
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Basically, 2 circuits sharing the same box. What is right or wrong with this plan?
That is acceptable.

Also, I would prefer not working with metal conduit and boxes, but I will if I have to. I would just need to ground the outlet to the conduit and then ground the conduit to a nearby copper pipe, right?
Grounding to a nearby copper pipe is not acceptable.



1) Because this is in an unfinished basement and the appliances will not be moved (ever), can I get by without using a GFI outlet?
No you may not.


Is your electrical system romex or metal?
 
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Old 08-04-14, 09:40 AM
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If the conduit run is continuous it is better practice to use individual conductors (THHN/THWN). Its easier to pull and you can use smaller conduit.You would use one green (one ground wire can be used by both receptacle), one gray, one white, one red, one black in " PVC conduit*. Both receptacles must be GFCI.

*One green, two blacks, and two whites could be used but making one circuit black and white and one red and gray makes it clear for a future repair person how it is wired. You could also use a multiwire circuit from two handle tied breakers, one green, one black, one red, one white.
 
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Old 08-04-14, 11:03 AM
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@bigboypete - If using a metal box or conduit, I have to ground the receptacle to the box first correct? What do I ground the metal box/conduit to?

@ray2047 - The conduit run would not be continuous. My current electrical system is all romex. The setup would be bare romex runs along the joists and I would then bring down a piece of conduit, metal or otherwise, along the wall that would terminate with a box containing the two (apparently GFI) receptacles.
 
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Old 08-04-14, 11:09 AM
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If using a metal box or conduit, I have to ground the receptacle to the box first correct? What do I ground the metal box/conduit to?
You can loop the ground wire around the ground screw and then connect it to the receptacle. Or just run the ground into the box and connect a pigtail to the receptacles and box and splice with a wirenut.
 
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Old 08-04-14, 11:20 AM
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You likely can find a two gang FSE box with 1" hub on it at the big box stores.
 
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Old 08-04-14, 11:54 AM
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2) Ground is always an important consideration, so since I am planning on running through plastic and each circuit will be a direct run back to the breaker box can I just ground off the bus bar in the breaker box?
Providing this is your main panel (first disconnect of the service) then yes, the EGC's will be on the neutral buss bar. There are other requirements that must be considered if this is a subpanel.
 
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Old 08-04-14, 12:12 PM
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You likely can find a two gang FSE box with 1" hub on it at the big box stores.
Yeah, finding the box isn't the problem. The problem is trying to find a FSE compatible 2-gang GFI cover that isn't some large outdoor waterproof monstrosity. I struck out at Home Depot and Lowes so maybe I'll try to find a local electrical supply company.

Providing this is your main panel (first disconnect of the service) then yes, the EGC's will be on the neutral buss bar. There are other requirements that must be considered if this is a subpanel.
This would go into the main panel, there are no subpanels in our house.
 
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Old 08-04-14, 12:16 PM
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Just a plastic two gang GFCI/GFCI plate should work. Like this:
[ATTACH=CONFIG]35883[/ATTACH]
 
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Old 08-04-14, 12:55 PM
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[ATTACH=CONFIG]35888[/ATTACH]

The FSE box above is the one I was looking at. The two receptacles would mount normally, but the cover uses the 4 outer screws. Like this pic below (only not metal and 2-gang).



This is what I am looking for and may just have to get it online:

[ATTACH=CONFIG]35889[/ATTACH]

ref: Mulberry Metal Products
 
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Old 08-04-14, 01:01 PM
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You do not need to use the 4 corner screws. You can just use a standard plate that attaches to the devices.

The picture you posted might be an explosion proof box. I doubt you want to buy that. $$$$$
 
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Old 08-04-14, 01:06 PM
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Why cant you just use the extra large 1900 box and a double GFCI raised cover and just bond the box? At least you wont be struggling to fit 2-GFCI's like you will be with that plastic stuff.
 
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Old 08-04-14, 02:35 PM
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A couple things:

The picture you posted might be an explosion proof box. I doubt you want to buy that. $$$$$
Well, if you're talking about the metal one, that was just to show the FS hole arrangement - the plastic box is like $5. I'm not sure what I was thinking about the hole arrangement I guess I'm not used to GFI outlets and their cover screw placement I've only needed to replace a couple of them at our house.

Why cant you just use the extra large 1900 box and a double GFCI raised cover and just bond the box? At least you wont be struggling to fit 2-GFCI's like you will be with that plastic stuff.
Googling....Googling.....Googling. Ah, I see. I was trying to avoid metal but it's probably not that much of big of a deal and I might find myself space constrained with the plastic molded box.

Regardless of the box the conduit will be mounted against a cinder block wall. Anything I need to know because getting a decent masonry drill bit?
 
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Old 08-04-14, 08:06 PM
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A hammerdrill will make it easier but is not necessary for just two or three holes. Ramset pins could also be used with a hammer.
 
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Old 08-05-14, 04:17 AM
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I'm getting a little of course here, so I appreciate anyone that is still hanging on.

My drill actually IS a hammer drill and it seems that the ramset pins require another tool (specific hammer), so I'll probably go the hammer drill route.

My (hopefully) final question is: The exterior walls in the basement are cinder block, but I do not know if it is standard practice to fill them with concrete or not. Is there any way to tell and would I have any issues using a masonry bit on a hollow cinder block wall, like making the surrounding parts crumble? Thanks.
 
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Old 08-05-14, 07:02 AM
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If the block is in good shape the hammerdrill will not cause an issue.
 
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Old 08-05-14, 07:55 AM
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would I have any issues using a masonry bit on a hollow cinder block wall
If you are buying the bit for your hammerdrill, I'd suggest you spend a buck or two more and buy a percussion bit intended to be used with a hammerdrill. It'll last a lot longer than a simple masonry bit. Here's an inexpensive one.

DEWALT 1/4 in. x 4 in. Carbide Tipped Percussion Drill Bit-DW5224 at The Home Depot
 
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