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Wiring through conduit/chase - what are maxiumum # of wires by code

Wiring through conduit/chase - what are maxiumum # of wires by code

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  #1  
Old 09-29-11, 02:11 PM
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Wiring through conduit/chase - what are maxiumum # of wires by code

Adding an accessory apartment and will be putting new wires through an existing wall chase. This is a two part question. 1. Since I'd prefer not to open the chase which was sealed between floors per code, is it OK to drill a hole to feed electrical PVC pipe up through the chase and then feed wires through this PVC? This of course would be sealed top and bottom with firestop goop once the wires are in place. And then 2. Is there a formula to determine the correct PVC pipe size based on the number and size of the wires? I'll be adding one 10/3, two 12/2 and two 14/2 wires. (The rest of the wiring was put in place when the original house was built, including the 8/3 for the range.) OK, so it's really a three part question - - Should the PVC pipe be perforated, in the section that will be between floors, to help transfer any heat build-up outside the pipe into the larger chase area?
 
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  #2  
Old 09-29-11, 02:28 PM
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There should be no more than two cables per insulated/firestopped hole, so with five cables you'll need three holes through the chase. The PVC is really unnecessary in this case.
 
  #3  
Old 09-29-11, 05:16 PM
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Each oocupant should have access to their panel. It may make sense to run a feeder between floors and install a panel in the apartment.
 
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Old 09-30-11, 01:05 PM
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@ibpooks - - Thanks for the info. I had no idea about this restriction.
 

Last edited by Margee; 09-30-11 at 01:06 PM. Reason: to direct the reply to one of the respnoders
  #5  
Old 09-30-11, 01:09 PM
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@pcboss - - Since this is an accessory apartment (used to be called in-law apartment) is it mandatory to have a separate panel? If this was a easy change I'd do it in a heartbeat and have a separate meter, too....
 
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Old 09-30-11, 04:47 PM
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I would probably be easier to just fish a single #2-2-4-6 SER cable up to the apartment and put in a 100A subpanel. This would be mandatory in some jurisdictions, but not in others. The code is not entirely precise when it comes to mother-in-law apartments, so it really boils down to what the local inspector enforces in the area.

There's really no way you could go wrong with the 100A panel option because that would be sufficient to make it a fully stand-alone apartment in terms of electrical code.
 
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Old 10-01-11, 02:53 PM
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@ibpooks - - I wish I had thought of this (putting in the sub panel) when I built the house and pre-wired part of this area. As it is I originally put in five circuits, the 10-3 50amp for the range, and four 20 amp circuits, one each for the kitchen, bathroom, bedroom and living areas. Of course I forgot the refrig needs it's own circuit. And due to the way the walls have been finished it's easier to bring another 20 amp up for additional kitchen outlets. Also I decided to wire and plumb for a stacked washer and dryer so there's another 20 amp and 30 amp. And for ease of rewiring the ceiling lights in the bathroom and bedroom area (that are already in place but on a switch with the rest of the overhead lights) I'm bringing up a 15 amp to handle those two, their switches and a new fan/light over the tub. Oh well, hindsight is almost always closer to 20/20. But of cours if the building inspector requires a separate panel tha's what I'll be doing. Thx for all your help.
 
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Old 10-01-11, 06:30 PM
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10-3 50amp
This circut needs to be 6/3g. 10/3 is only good for 30A.
 
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Old 10-01-11, 08:19 PM
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The refrigerator does not need a dedicated circuit under the NEC. Does your area have a local amendment?
 
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Old 10-06-11, 12:59 PM
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@Pcboss - - Thanks for the info - - When I built the house in 2004 (Connecticut) the building inspector (BI) requested a separate circuit. CT uses the national codes. I noticed in more recent publications that this no longer seems to be necessary but decided to err on the side of being conservative ie giving the BI again what he wanted back then. One of the 20 amp lines I'm bringing up for the kitchen would be very convenient for me to add the refrigerator to. The only other items on the circuit will be two outlets for small countertop appliances (I haven't decided whether to put in duplex or single outlets). I was going to make this a GFCI by using a GFCI breaker. Is this ok? When I built the house the BI told me even if I put in a GFCI breaker I also needed to put in GFCI outlets at the beginning of both circuits or just put in the GFCIs at the beginning of the runs and forget about the GFCI breakers. Has this code chaged? It seems a waste to put GFCI outlets on a GFCI breakered run. What am I missing?
 

Last edited by Margee; 10-06-11 at 01:23 PM. Reason: direct comment back to commentor pcboss
  #11  
Old 10-06-11, 01:09 PM
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@Justin Smith - - Opps, typo on my part. Right you are, the range is on a 50A circuit using 6/3. And right again, the 10/3 is for 30A circuit, in my case this is for the dryer.
 

Last edited by Margee; 10-06-11 at 01:11 PM. Reason: direct comment back to commentor
  #12  
Old 10-06-11, 02:44 PM
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The GFI protection can be provided by either a GFI breaker or a GFI receptacle. There is no need for both.

The refrigerator can share one of the 20 amp countertop circuits under the NEC.
 
  #13  
Old 10-07-11, 02:11 PM
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@pcboss -- The information you've been kind enough to give me is much appreciated. Sounds like the BI may request a sub panel. Is there a maximum run from the main panel to a sub? I'm assuming 100A sub panel will be requested. I'll run the wire but I don't touch panels - - just not confident enough to do that part, I'll get a pro in for that.
 
  #14  
Old 10-07-11, 02:25 PM
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There is no maximum distance, but very long distances require larger wires. You can go at least 100 - 125' feet without increasing wire size.

You will almost certainly want to use a #1 aluminum SER or #2 copper SER cable for a 100A apartment subpanel. The aluminum wire is a little harder to work with, but usually cheaper.
 
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