Multi Voltage conductors in same conduit

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The NEC requires the two different voltage systems to be identified by color and a legend to be placed at the panels.
 
The only thing that changes, assuming that the voltages are 600 volts or less, is the requirement to identify the neutral conductor by system when there are two or more neutral conductors from different systems in the same raceway or enclosure.
 
200.6(D), 210.5(C), 215.12(C)
These are the section numbers that have the requirements for identification.

They do not have to be identified by color. The identification means are spelled out in the sections I provided. Color is probably the most common method.

300.3(C) is the section that permits the inclusion of more than one "system" within raceways and enclosures.

Be careful, as there are other sections that have some bearing on this as well. Such as, 404.8(B).
 
Pierre C Belarge said:
300.3(C) is the section that permits the inclusion of more than one "system" within raceways and enclosures.
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Seeing as were being picky 300.3(C) does not allow it.

300.3(C) places restrictions on a practice that is not prohibited elsewhere in the code. :cool:
 
One important note, be careful about the insulation used on the lower voltage system, it must me insulated to the highest voltage in the raceway.

300.2 Limitations.
(C) Conductors of Different Systems.
(1) 600 Volts, Nominal, or Less. Conductors of ac and dc circuits, rated 600 volts, nominal, or less, shall be permitted to occupy the same equipment wiring enclosure, cable, or raceway. All conductors shall have an insulation rating equal to at least the maximum circuit voltage applied to any conductor within the enclosure, cable, or raceway.
 
iwire said:
Seeing as were being picky 300.3(C) does not allow it.

300.3(C) places restrictions on a practice that is not prohibited elsewhere in the code. :cool:
Click to expand...


[FONT='Times-Bold','serif']"(C) Conductors of Different Systems.[/font]
[FONT='Times-Bold','serif'](1) 600 Volts, Nominal, or Less. [/font][FONT='Times-Roman','serif']Conductors of circuits[/font]
[FONT='Times-Roman','serif']rated 600 volts, nominal, or less, ac circuits, and dc circuits[/font]
[FONT='Times-Roman','serif']shall be permitted to occupy the same equipment wiring[/font]
[FONT='Times-Roman','serif']enclosure, cable, or raceway. All conductors shall have an[/font]
[FONT='Times-Roman','serif']insulation rating equal to at least the maximum circuit voltage[/font]
[FONT='Times-Roman','serif']applied to any conductor within the enclosure, cable, or[/font]
[FONT='Times-Roman','serif']raceway."[/font]





As long as the conductors have the proper insulation rating, they are permitted in the same conduit.


(Sorry for all of the editing, I tried to clean this up, without any luck)
 
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There is no place in the NEC that prohibits the mixing of different system conductors.

All 300.3(C) does is restrict the installation of different systems to conductors of sufficient voltage rating.

If 300.3(C) was removed from the NEC I could still mix systems.
 
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