Conduit fill 1/2 inch EMT

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woodduder said:
Might be a mini split. The 2 #8 and #10 feed the CU and then the CU feeds the mini split AHU with the 2#12 back inside the building. The 14 would be the control wire from the CU to the AHU. Lots of these in my area, although we keep the control a #12, but it likely doesn't need to be.

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You're probably right. I've pulled for all that before but used all 12awg because we never have 14 on site.

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Leaves me more quest I ns than answers

Leaves me more quest I ns than answers

Honestly you would have to use the circ. mil calculations to find that out. There are other factors, I know. Is is less than a 2 foot run of conduit? Fill her up to 100% if it is. I think you can do it. And you have to pull a ground anyway you can't use emt or any pipe alone for a ground anymore. That's a good question though, are all of them current carrying conductors or no? Is one a ground? Why can't you just swap it for some 3/4? This is a rookie question bro. Get er done
 
Tom the lectrician said:
Honestly you would have to use the circ. mil calculations to find that out. There are other factors, I know. Is is less than a 2 foot run of conduit? Fill her up to 100% if it is. I think you can do it. And you have to pull a ground anyway you can't use emt or any pipe alone for a ground anymore. That's a good question though, are all of them current carrying conductors or no? Is one a ground? Why can't you just swap it for some 3/4? This is a rookie question bro. Get er done
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Tom it may be a rookie question but you cannot fill it up 100%

(4) Where conduit or tubing nipples having a maximum
length not to exceed 600 mm (24 in.) are installed between
boxes, cabinets, and similar enclosures, the
nipples shall be permitted to be filled to 60 percent of
their total cross-sectional area, and 310.15(B)(3)(a) adjustment
factors need not apply to this condition.
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How many of your employees play this game with you? Or are you an inspector seeing what's still out there with everybody googling the answers. I bet there is a conduit fill app too. I personally been out of the construction game for a while, brushing up on troubleshooting and instrumentation, but practically I would say it's not worth the time or effort, run a bigger pipe so you have room for spares.
 
Tom the lectrician said:
Honestly you would have to use the circ. mil calculations to find that out. There are other factors, I know. Is is less than a 2 foot run of conduit? Fill her up to 100% if it is. I think you can do it. And you have to pull a ground anyway you can't use emt or any pipe alone for a ground anymore. That's a good question though, are all of them current carrying conductors or no? Is one a ground? Why can't you just swap it for some 3/4? This is a rookie question bro. Get er done
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Can you provide a code reference that says that?
 
JFletcher said:
The #14 would have to be a neutral b/c the #10 would be the grounds for the dual 8s, and you only need one EGC in the conduit... unless the EMT is serving that role. but then why pull neutrals to eqpt that doesnt need it? especially when it blows your conduit fill???

"Short run" would tell me the 12s werent run for VD...

On a 15A circuit, can you run a #14 non-CCC neutral or ground if the ungrounded conductors are #12? I thought the answer was in 250.122....
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could be 2 - #8 for the AC unit, 10 AWG ground, and a 15 and 20 amp multiwire branch circuit being pulled in there, to arrive with the questionable #14. Neutral of that MWBC would need to be 12 AWG minimum.

woodduder said:
Might be a mini split. The 2 #8 and #10 feed the CU and then the CU feeds the mini split AHU with the 2#12 back inside the building. The 14 would be the control wire from the CU to the AHU. Lots of these in my area, although we keep the control a #12, but it likely doesn't need to be.

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Unless temperature derating comes into play, a unit that requires 8AWG supply doesn't exactly sound "mini" to me;)

Tom the lectrician said:
Honestly you would have to use the circ. mil calculations to find that out. There are other factors, I know. Is is less than a 2 foot run of conduit? Fill her up to 100% if it is. I think you can do it. And you have to pull a ground anyway you can't use emt or any pipe alone for a ground anymore. That's a good question though, are all of them current carrying conductors or no? Is one a ground? Why can't you just swap it for some 3/4? This is a rookie question bro. Get er done
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2 foot or less can only be filled to 60% not 100. Unless you have a local rule, NEC still recognizes metal raceways for use as an equipment grounding conductor.
 
tx2step said:
Nope, just don't have my book with me. You can check my profile.

You can only put 3 #8 or 5 #10s in a half inch, so I'm pretty sure it's overfilled and pass inspection. I don't think you could pull it without skinning the insulation, anyway.
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I didn't calculate the fill, but another member has and says it is not much over 40% filled.

Whether or not you can pull it without skinning conductors isn't exactly one of those definite things, one can skin conductors at 25% fill if you don't use some care handling things, or if it is a straight run one may get 75% fill pulled in there without too much troubles even though it is not compliant.
 
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