Upsized wires for Voltage drop , now to big to land!

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pms_electric

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I am doing a project where the run is 500ft (emt indoors). The print calls for #4's on a 20amp breaker. I know that this is correct for the voltage drop but is there any point at the end That I can drop down to land on recpts. , switches, motors. What are the rules for this?
 
I've never used them on a 20 amp breaker, but on larger breakers you can use a pin terminal. I'm not sure if that is the correct term, but it is a compression adapter that somehow maintains the rating of the wire. You can change from copper to aluminum with the correct fitting. Look up Ilsco.
 
Use a NSI polaris IT-4 to go from 4 to 12 in the panel. Got drop ceiling? Do the same in a J-box above the ceiling and branch out to devices with 12.
 
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pms_electric said:
I am doing a project where the run is 500ft (emt indoors). The print calls for #4's on a 20amp breaker. I know that this is correct for the voltage drop but is there any point at the end That I can drop down to land on recpts. , switches, motors. What are the rules for this?
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The short piece that would be added on at the ends, as Chris suggested, will not make a significant difference at all.
 
I can splice in the panel to drop down, my concern is the load end, what i would like to do is run all of my wires(15 #4s) in a 2" and split off from a box to the individual locations when I get 20-30 feet away. is there a code that allows/not-allows this?
 
pms_electric said:
I can splice in the panel to drop down, my concern is the load end, what i would like to do is run all of my wires(15 #4s) in a 2" and split off from a box to the individual locations when I get 20-30 feet away. is there a code that allows/not-allows this?
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Sounds fine.
 
Just remember that the NEC does not require voltage drop compensation for this type of installation.
 
pms_electric said:
. . . what i would like to do is run all of my wires(15 #4s) in a 2" and split off from a box to the individual locations when I get 20-30 feet away.
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If you use a larger wire for part of a run, you can transition back to the smaller wire at any point you wish. But if you wish to run fifteen #4 wires in a 2" conduit, you might have some difficulties. For example, with schedule 80 PVC and with THHN wire, a 2" conduit can only handle 14 conductors.
 
charlie b said:
If you use a larger wire for part of a run, you can transition back to the smaller wire at any point you wish. But if you wish to run fifteen #4 wires in a 2" conduit, you might have some difficulties. For example, with schedule 80 PVC and with THHN wire, a 2" conduit can only handle 14 conductors.
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He did mention 2" EMT which can be filled with up to 16-#4 THHN condcutors. For a 500'run that might be a difficult pull.
 
I never thought about it but in a situation like this derating won't even be an issue since the wire is so large anyway.
 
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