I have an installation manual from a generator manufacturer that says low voltage control wires and power conductors from a gen set can be run in the same raceway provided the conductor insulation is of equal voltage rating. With that being said, is it a code violation to have utility power branch circuit conductors occupy a exterior junction box that has the gen set wiring pass through it? I have a 12"x12" pvc j box that is being used as as part of a raceway containing gen set wiring and I would like to feed into it with utility branch circuits to get to some exterior equipment requiring power. This is a residential stand by power system that is installed at a single family dwelling. If it is a violation, could someone post where I could find it in the code. Thanks.
generator/utility circuits
- Thread starter nizak
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- Placerville, CA, USA
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- Retired PV System Designer
The control wires cannot share a raceway with unrelated power conductors.
Tapatalk!
Tapatalk!
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- Placerville, CA, USA
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- Retired PV System Designer
The power wires are feeders, not service wires and so could share with any other non-service power wires (assuming compatible voltages).
Tapatalk!
Tapatalk!
It really depends on the classification of your "low voltage" circuits. 300.3(C) allows it, but quite often the control wiring is a Class 2 circuit and Art 725.136 (or relative Art 725 section) prohibits the practice.
What brand of generator ? (Most of the ones I see require separate raceways)
What brand of generator ? (Most of the ones I see require separate raceways)
- Location
- Massachusetts
It depends on the specifics of the installation.
goldstar
Senior Member
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- New Jersey
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- Electrical Contractor
The general rule is that you cannot or should not but a lot depends on the manufacturer and what they specify in their manuals. For instance, a Generac "Essential Circuits" system comes with a 30', pre-manufactured whip on the xfer/breaker panel that contains the generator feeder wiring as well as the wiring for the control and sensing circuits. The whip from the generator to the connection port has the same wiring. Now, a Generac "Whole House" system does not come with any pre-made whips. You have to fabricate them yourself. So, you have to ask the question "If Generac can manufacture whips like these and be Code compliant why can't I make my own "? Some inspectors will allow it because the Generac manuals don't specifically state that you cannot.
Now, if you install a Kohler or B & S system I believe they specify that these conductors have to be run in separate raceways. I'm sorry I didn't specifically answer your question but based on my experience with these generators over the last 8 years or so I've never had a problem (functionally speaking) when the conductors were combined. The fact that I haven't been cited for it doesn't mean that what I did was correct either.
Now, if you install a Kohler or B & S system I believe they specify that these conductors have to be run in separate raceways. I'm sorry I didn't specifically answer your question but based on my experience with these generators over the last 8 years or so I've never had a problem (functionally speaking) when the conductors were combined. The fact that I haven't been cited for it doesn't mean that what I did was correct either.
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