Ac And Dc

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Why not? I see no NEC passage that prohibits it as long as the conductors are all insulated for at least the highest voltage present. See 300.3(C)(1) which specifically permits AC and DC in the same conduit, etc.
 
You are permitted to do it as long as the cable insulations meet the voltage requirements, but it is a poor design IMO because of the induction problems likely to be encountered on the DC circuits.
 
barbeer said:
The OP said nothing of the NEC. I was thinking as dereckbc was with "noise" or problems with the different waveforms.
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It depends on the voltage level of the circuits.

24VAC + 24VDC - no big deal
120VAC control + 230VDC power - no big deal either
120VAC inductive loads + 5VTTL- big problem
 
There are restrictions, both NEC and other standards, against installing some communication cables with power conductors. See 800.52 for some restrictions, but this does not apply to all DC circuits. There is no restriction against installing most DC control circuits in a conduit with AC circuits. There are very few things in the NEC that are either yes or no, most are maybe or sometimes. A very wise inspector told me when I was just starting in the trade: "If the NEC tells you that you can't do something that you want to do, you probably have not read far enough. There is usually an exception or something that tells you that it is OK". I have found that is often the case.
 
frank melillo said:
Should Ac And Dc Be Installed In The Same Conduit.
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Happens all the time .... simplest example: Smoke alarms in a dwelling unit.
Granted, the "conduit" is NM or AC, but the principle is the same.


Where are you headed with this? (This isn't just a simple question, right? :D)
 
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