Line/Switch leg in EMT

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Hey guys, I'm probably over thinking this, but want to double check myself. Have a shop to light, panel is on one side of the room, door is on the other side. Normally I try to avoid putting my line in the same conduit as my switch legs to avoid heating. This job would work better to put them all in the same conduit. But didn't know if that's a good idea or if I should run a dedicated pipe for my lines, to the switch box, then back up to the lights. There will be 2 circuits, so in my 3/4 emt there will be 2 lines, 2 switch legs, and 2 neutrals + ground. Thanks in advance!

Edit - each circuit is looking at a 14 amp load.
 

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infinity said:
There is no reason to run more than one raceway. You have 6 CCC's so even with derating you're fine with #12 AWG conductors.
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And if the neutrals are there only for in case of occupancy sensor switch that requires a neutral, he kind of sort of only has 4 CCC's though same ampacity adjustment still applies.

If this is 12 AWG conductors (kind of assuming it is) he still has enough conductor for 50% ampacity adjustment if load is only 14 amps on each one of them.
 
kwired said:
If this is 12 AWG conductors (kind of assuming it is) he still has enough conductor for 50% ampacity adjustment if load is only 14 amps on each one of them.
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He mentioned shop lighting so wouldn't that be a continuous load meaning 14 amps*125% would be a minimum conductor ampacity of 17.5 amps?
 
infinity said:
He mentioned shop lighting so wouldn't that be a continuous load meaning 14 amps*125% would be a minimum conductor ampacity of 17.5 amps?
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Correct, I forgot to consider that. Does still work for up to 80% adjustment so he could still have three more CCC's in what he's got there before adjustment would require larger conductors. Though I myself think the neutrals shouldn't count if all they supply is the electronics of an occupancy sensor, but I don't think NEC has such an allowance for that situation.
 
Yeah they'll be 6 ccc for sure, they'll be running on 120v. I'm guessing the lights will be on a few hours here and there, maybe more on the weekends. I figured all this stuff is designed to handle it so I'll run with it.
 
I have no idea how long your runs are but if significant I would install 2 power pack relays at the first junction box then run a class 2 cable to the switches. Saves on wire and voltage drop.

You could even spend a little more for Lutron Relay's and install Pico switches.
 
User Name said:
Yeah they'll be 6 ccc for sure, they'll be running on 120v. I'm guessing the lights will be on a few hours here and there, maybe more on the weekends. I figured all this stuff is designed to handle it so I'll run with it.
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Unless you have load at or beyond the switch location those neutral conductors carry no current, just the two "switch loop" conductors per switch are all that is carrying current. From what I understand this is a raceway from lighting location to switch location though so other than say there were occupancy sensors for switches, the neutrals have nothing to terminate to on the switch end.
 
I might not understand...the neutrals should have load or some...if I run a neutral to the switch box yeah no load there, but the main trunk of pipe that will have the line, switch leg, and neutrals will all be flowing with something right? That's the part I'm most concerned about, not so much the drop down to the switches.
 
User Name said:
I might not understand...the neutrals should have load or some...if I run a neutral to the switch box yeah no load there, but the main trunk of pipe that will have the line, switch leg, and neutrals will all be flowing with something right? That's the part I'm most concerned about, not so much the drop down to switches.
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Sounds like you circuit your neutral is carrying the lighting load of the circuit and it's therefore counted as a CCC.
 
User Name said:
I might not understand...the neutrals should have load or some...if I run a neutral to the switch box yeah no load there, but the main trunk of pipe that will have the line, switch leg, and neutrals will all be flowing with something right? That's the part I'm most concerned about, not so much the drop down to the switches.
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Ampacity adjustment for conductors in a particular segment of raceway only need to consider the current carrying conductors within that segment. Also a neutral that only carries unbalanced current is not considered a CCC for ampacity adjustment reasons in most instances. Control and signaling conductors when permitted with power conductors aren't counted as CCC's either. A neutral only supplying an occupancy sensor only carries control/signal type current levels though I don't know if NEC sees it that way. Isn't really much of a problem much of the time unless you have a significant number of conductors in a raceway to a switching location.
 
At first I thought wait neutrals are ccc so you got to count them...but I looked it up and sure enough 310.15(E)(1) A neutral conductor that carries only the unbalanced current from other conductors of the same circuit shall not be required to be counted.... Thats a new one to me lol.

I would say though that a neutral IS a ccc you're just not required to count it. Personally I think it would still be a good idea to count it as one, nothing wrong with having a little extra room when sizing a pipe run right? Unless you're bidding something kind of close....
 
User Name said:
At first I thought wait neutrals are ccc so you got to count them...but I looked it up and sure enough 310.15(E)(1) A neutral conductor that carries only the unbalanced current from other conductors of the same circuit shall not be required to be counted.... Thats a new one to me lol.

I would say though that a neutral IS a ccc you're just not required to count it. Personally I think it would still be a good idea to count it as one, nothing wrong with having a little extra room when sizing a pipe run right? Unless you're bidding something kind of close....
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You have a two wire circuit with a hot and neutral providing power to the lighting how is the neutral not a CCC?
 
Code defines Neutral conductor as "the conductor connected to the neutral point of a system that is intended to carry current under normal conditions." So not sure how the code is says its a CCC and yet says we don't have to count it as a CCC.
 
User Name said:
Code defines Neutral conductor as "the conductor connected to the neutral point of a system that is intended to carry current under normal conditions." So not sure how the code is says its a CCC and yet says we don't have to count it as a CCC.
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Where does it say that it doesn't count? Don't you have a two wire circuit?
 
User Name said:
At first I thought wait neutrals are ccc so you got to count them...but I looked it up and sure enough 310.15(E)(1) A neutral conductor that carries only the unbalanced current from other conductors of the same circuit shall not be required to be counted.... Thats a new one to me lol.

I would say though that a neutral IS a ccc you're just not required to count it. Personally I think it would still be a good idea to count it as one, nothing wrong with having a little extra room when sizing a pipe run right? Unless you're bidding something kind of close....
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We don't count the neutral as CCC for services/feeders in nearly all instances, even if it doesn't cross the mind it isn't needed.

For a three phase four wire wye circuit it would otherwise bump you up from no adjustment needed for 3 CCC's to 80% adjustment needed for 4 CCC's, even with no other conductors in same raceway.

The low amount of current on control signaling circuits doesn't contribute significant enough amount of heat to the raceway is why those aren't counted. I'd need to read carefully but I doubt NEC would outright call the neutral to a occupancy sensor strictly a control conductor though it essentially is carrying similar current levels if the occupancy sensor is all it is carrying load from.
 
User Name said:
Code defines Neutral conductor as "the conductor connected to the neutral point of a system that is intended to carry current under normal conditions." So not sure how the code is says its a CCC and yet says we don't have to count it as a CCC.
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Not counting it as a CCC only applies to making ampacity adjustments per 310.15(C).
 
kwired said:
We don't count the neutral as CCC for services/feeders in nearly all instances, even if it doesn't cross the mind it isn't needed.

For a three phase four wire wye circuit it would otherwise bump you up from no adjustment needed for 3 CCC's to 80% adjustment needed for 4 CCC's, even with no other conductors in same raceway.

The low amount of current on control signaling circuits doesn't contribute significant enough amount of heat to the raceway is why those aren't counted. I'd need to read carefully but I doubt NEC would outright call the neutral to a occupancy sensor strictly a control conductor though it essentially is carrying similar current levels if the occupancy sensor is all it is carrying load from.
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I guess I could see your point there on the service feeders that could be handy.

Should note my install has no occ sensors or such, but I do get what you're saying.
 
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