Homeruns

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Dennis Alwon

Dennis Alwon

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horsegoer said:
Sorry to beat a dead horse here. Should'nt the VD be calculated for the entire length of wire/circuit..including the wiring of the devices or is it understood that the devices(20a recept with 1a loads) can more than likely be wired in #12 but it will be the "homerun" that may need to be adjusted. Just not understanding why part of the run can be #12's..guess it has something to do with the devices????
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If a major portion of the run is done with #10 then the VD would be insignificant to each device in #12. Certainly if the devices were daisy chained for another 200 feet that could be an issue.

Think of it this way. By running #10 from the panel to the first device you eliminated most of the voltage drop so now the rest of the circuit can go back to using #12.
 
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Alwayslearningelec

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infinity said:
The NEC does not require voltage drop compensation for this type of load. It's a design issue.
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Ahhhh...that clears it up. So say there is no mention of HR's having to be #10 but on the panel schedule each 20a/1p breaker shows 2#10's & 1#10g w/3/4" conduit and this is for the gen conv. receptacles. How would you interpret/wire that. To me that means a #10 homerun....but again I would try to take the #12's as far as I could to a homerun box then run all my conduits from that box to the panel. THanks....
 
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roger3829

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Torrington, CT
horsegoer said:
Ahhhh...that clears it up. So say there is no mention of HR's having to be #10 but on the panel schedule each 20a/1p breaker shows 2#10's & 1#10g w/3/4" conduit and this is for the gen conv. receptacles. How would you interpret/wire that. To me that means a #10 homerun....but again I would try to take the #12's as far as I could to a homerun box then run all my conduits from that box to the panel. THanks....
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Isn't the panel the homerun box? The home run is from the panel to the first device, so.............It doesn't matter how many boxes are placed in between for splicing or for changing wiring methods.
 
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cdslotz

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Ok, let's saya spec limits (3) cicruits to a conduit and says all homeruns must be #10 wire. If you have say (12) circuits in an area about 150' away why would you ever run a homerun out to that location? Would'nt you run the homerun 10-20' feet out then run the #12's to the location.......keeping the homeruns as short as possible? THanks.
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If that is what the spec says, then I would run (4) 3/4" each with 1-hot, 1-N, and 1-EG. Then I would continue around the rooms with my HR grid, then drop to the recepts with #12.
End of story.
I have a job currently with that exact verbiage, however, it goes on to say "Where more than 3 current carrying conductors in a raceway, use larger conductors and appropriate size raceway to meet article 310 of the NEC."

So it gives me an out to that requirement. Check your specs
 
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Alwayslearningelec

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cdslotz said:
If that is what the spec says, then I would run (4) 3/4" each with 1-hot, 1-N, and 1-EG. Then I would continue around the rooms with my HR grid, then drop to the recepts with #12.
End of story.
I have a job currently with that exact verbiage, however, it goes on to say "Where more than 3 current carrying conductors in a raceway, use larger conductors and appropriate size raceway to meet article 310 of the NEC."

So it gives me an out to that requirement. Check your specs
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Ok so when the spec says "all homeruns to be #10" do you think they reallly mean or enforce from the last device because that was is what a homerun is...right??? If not then you can go from the last device to a "homerun box" with the #12's then run your #10's. Hey.... saves on some #10 wire...
 
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roger3829

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I'm at a loss. I have no idea what a "homerun box" is.

It seems to me that you're trying to cheat the job specs. by not running #10 wire as they call for.
 
Dennis Alwon

Dennis Alwon

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Last time I say this. The homerun is generally the run from the panel to the first device. Now if a jb were installed in a ceiling near to where the circuit is run I am sure the EE would okay the # 10 wire to that JB and then drop down with #12 to the outlets below.
 
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Alwayslearningelec

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Dennis Alwon said:
Last time I say this. The homerun is generally the run from the panel to the first device. Now if a jb were installed in a ceiling near to where the circuit is run I am sure the EE would okay the # 10 wire to that JB and then drop down with #12 to the outlets below.
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Sorry..thanks.
 
iwire

iwire

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Massachusetts
I don't think what anyone of us thinks means that much. Only the person that produced the specification can tell us what they intended.

A simple RFI can fix that .......... it can also lock you firmly into something so consider all the possibilities before sending.
 
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cdslotz

Senior Member
horsegoer said:
Ok so when the spec says "all homeruns to be #10" do you think they reallly mean or enforce from the last device because that was is what a homerun is...right??? If not then you can go from the last device to a "homerun box" with the #12's then run your #10's. Hey.... saves on some #10 wire...
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I can't read all of your spec, but the example spec I referenced also said:
"minimum wire sizes shall be in accordance with other requirements of the spec and as follows: for 20A branch circuits #12 gauge, except at runs greater than 100 feet from the panel to the first outlet box, shall be #10 gauge." .
Now to ME, that reads the FIRST outlet box. You can't get hung up on the definition of a home run. Instead focus on the requirement of the spec.
If your spec is not clear, and you already have the job, talk to the engineer. But read every line and understand how you want to steer the answer. If the spec contradicts itself, or is completely vague, point out how YOU interpreted it. He may cut you some slack. If you just ask what he means or requires, you'll probably get the answer you're not looking for.
 
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Alwayslearningelec

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NJ
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cdslotz said:
I can't read all of your spec, but the example spec I referenced also said:
"minimum wire sizes shall be in accordance with other requirements of the spec and as follows: for 20A branch circuits #12 gauge, except at runs greater than 100 feet from the panel to the first outlet box, shall be #10 gauge." .
Now to ME, that reads the FIRST outlet box. You can't get hung up on the definition of a home run. Instead focus on the requirement of the spec.
If your spec is not clear, and you already have the job, talk to the engineer. But read every line and understand how you want to steer the answer. If the spec contradicts itself, or is completely vague, point out how YOU interpreted it. He may cut you some slack. If you just ask what he means or requires, you'll probably get the answer you're not looking for.[/QUOT

Thanks a lot CD
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