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Posted By: MikeW Mixing DC with AC conductors? - 08/10/05 10:33 AM
Does the NEC allow 24vdc wires to be run in the same conduit with 120vac conductors?

What code section(s)?

thanks
Posted By: resqcapt19 Re: Mixing DC with AC conductors? - 08/10/05 11:21 AM
Mike,
Look at 300.3(C)(1), but make sure that you read the FPN that follows that section.
Don
Posted By: gfretwell Re: Mixing DC with AC conductors? - 08/10/05 04:44 PM
Just remember that when you mix voltages in an enclosure or raceway you lose any latitide you might have had for "low voltage" in art 725. Everything is now treated like line voltage.
Posted By: pauluk Re: Mixing DC with AC conductors? - 08/13/05 12:17 PM
300.3 contains a similar requirement for this situation to one we have here -- That all conductors must be insulated for the highest voltage present.,
Posted By: resqcapt19 Re: Mixing DC with AC conductors? - 08/14/05 01:28 AM
Paul,
You have to read and apply the FNP that follows the section that you have cited. The section doesn't really mean what it says.
Don
Posted By: pauluk Re: Mixing DC with AC conductors? - 08/14/05 12:12 PM
Oh boy, I hadn't even started to read 725 before now. The definitions for class 2 and 3 circuits seem overly complex. This section is going to take some studying. [Linked Image]
Posted By: iwire Re: Mixing DC with AC conductors? - 08/14/05 12:43 PM
Paul,

Quote
The definitions for class 2 and 3 circuits seem overly complex. This section is going to take some studying

I wish you well, you must be a gluten for punishment if you want to try to make heads or tails of 725. [Linked Image]

Bob
Posted By: Rhino Re: Mixing DC with AC conductors? - 08/14/05 09:29 PM
I wonder wether there are some practical issues at play as well.Such as some current being imposed (through induction)on the DC circuit causing havoc with the circuits on the DC power run.
To be safe i would go with the rule of thumb of not combining one with the other.
Along the lines of even if it is permissable -should it really be done??
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