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enter image description hereI'm working on running some SE cable from a breaker box to a new 220V 14-50R receptacle. The old receptacle was not located within the area specified by our new electric range.

I am using TYPE SE STYLE R with four 6 AWG AL wires. One wire is an unshielded ground, the others have XHHW-2 insulation. One question I have is related to the number of bends allowed in the cable. In my earlier readings of various articles I thought I saw something about a limit in the number of bends. But at that time things were very foggy to me as opposed to being just a bit foggy now. Here are a couple of pictures from different perspectives. Cable with Clamp in place[![][1]]3

A reason for two of the bends is to accommodate a cable clamp which I think must be within 12 inches of where the cable enters an electrical box. The only way I could see having the clamp and reducing the number of bends is add another 2x4 which I think would then put the clamp more in line with the straight line routing of the cable. Any thoughts on this? Thanks in advance. Jim

JimCzek
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    You got an answer on the question, but note that those holes in the joists look too close to the edge. I believe they must be 2 inches or more from the edge, and IMO really are best in the middle, near the neutral axis. – Tim B Jan 04 '20 at 21:19
  • Tim B: I might have this wrong but here's what I found regarding bored holes and SE cable: NEC 338.10(4)(a)(1) refers to Part 2 of article 334. 334.17 ("Through or Parallel to Framing Members") refers to 300.4. 300.4(A)(1) mentions bored holes through joists. It states: "holes shall not be bored so that the edge of the hole is not less than 32 mm (1 1/4 in.) from the nearest edge of the wood member." I also see that 334.15(C) ("In Unfinished Basements and Crawl Spaces") states cables no smaller than two 6 AWG or three 8 AWG conductors can run directly under the lower edge of the joists. – JimCzek Jan 04 '20 at 23:31
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    Check IBC instead of NEC, which may only address electrical safety. Searching quickly, this quotes the IBC, and says 2 inches: http://www.co.routt.co.us/DocumentCenter/View/61/Notching-and-Boring-Allowances-for-Lumber?bidId= – Tim B Jan 05 '20 at 02:50
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    I think you have too many "not"s in your hole position sentence. Canadian regs say the hole must be at least 1 1/4 inch from the face of a stud. – Peter Bennett Jan 05 '20 at 07:01
  • yeah, 1-1/4" is to protect the wire from future nails. but the 2" is for structural integrity – Jasen Jan 05 '20 at 07:05
  • Why are you using aluminum for a new circuit? Presumably this is a 40A breaker and not a 50A? – J... Jan 05 '20 at 13:26
  • Peter Bennett: Yes I did add an extra "not" while type the text. I'm accessing the NEC via nfpa.org free access so I can't copy and paste. Thanks – JimCzek Jan 06 '20 at 00:49
  • Tim B, Jasen: Thanks for pointing this out. The holes I am using had an older 3 conductor (no ground) cable and were there when I purchased the house. On top of that the older outlet was not within the area specified by LG. I'm in the process of setting up an appointment with the township for an inspection. At this point it doesn't seem like I'd add to the structural integrity by drilling another series of holes to meet the 2" requirement. – JimCzek Jan 06 '20 at 00:57
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    Right. The issue isn’t the wire being too close to the edge, but the existence of the hole itself. So a new hole wouldn’t improve that. I pointed it out in case you had made them, that you’d make future holes more toward (or ideally at) the center. – Tim B Jan 07 '20 at 13:01
  • Thanks Tim. I will follow your guidance when new routing is required. I have a separate but related question if I may. I was told that "soon" 220V appliance outlets will have to have GFI protection. Do you know anything about that? Thanks. – JimCzek Jan 08 '20 at 15:40
  • @JimCzek make that a new question, if you find it hasn’t already been asked. (I can’t address it directly, as I’m an engineer, not an electrician) – Tim B Jan 16 '20 at 01:01

2 Answers2

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The NEC does not restrict the number of bends on SE cable. Raceway methods restrict bends to limit stress on wire being pulled through the raceway.

NoSparksPlease
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    NoSparksPlease - Again, thank you! – JimCzek Jan 04 '20 at 19:38
  • I might mention that there is a minimum bending radius to prevent stress on the insulation. The minimum bending radius for cables with shielded conductors is twelve times the diameter of one phase conductor or seven times the overall diameter, whichever is greater. – Retired Master Electrician Jan 05 '20 at 14:54
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They don't care about cable bends. So you're fine.

The limit on bends applies to conduit.

The conduit must be built out before the wires are pulled through it. Experience is that if you try to pull through too many bends, the pulling forces become rather extreme, and start to cause injury/damage to the wires you are pulling. So they require accessible points at intervals (mind you, they must stay accessible forever, can't be buried behind drywall etc.) They had to pick some number, so they chose 360 degrees of bend (in practice, four 90's) between accessible points. For novices doing their own pulling, I recommend more like 150 degrees tops, preferably 90.

Harper - Reinstate Monica
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