Dimming Wires

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don_resqcapt19

don_resqcapt19

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mstrlucky74 said:
So can't run the 0-10v dimming wires with 120v power if the dimming wires are 600v insulation?
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If
If the 0-10 volt dimming circuit is a Class 2 circuit you cannot run it with the 120 volt power no matter what the insulation rating of the dimming circuit conductors it.
 
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mstrlucky74

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don_resqcapt19 said:
If
If the 0-10 volt dimming circuit is a Class 2 circuit you cannot run it with the 120 volt power no matter what the insulation rating of the dimming circuit conductors it.
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Thanks. But 725.136, to me, doesn't seem like it addresses the insulation ratings and that, even if they are both rated 600v, you can't combine. Where is that listed?

And again, on a very large job with full emt conduit and lots of 0-10v fixtures I just can't see them running two separate conduits, one for power and one for dimming. They have ot be doing it differently and I'm not talking about the re-classifying route. Some engineer must have come across this and know.
 
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don_resqcapt19

don_resqcapt19

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augie47 said:
don, If you use Class 2 control, maintain spacing in your j box, will 725.136(I)(2) not allow you to use this cable to the fixtures as it provides a fixed non-conductor seperation

https://www.mysouthwire.com/medias/...duct-specifications/h33/h58/8854089400350.pdf
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That cable is permitted for that application. There are a couple of listed cables of that construction. It is my understanding that those cables are based on 725.136(I)(1) with the control cable having a jacket that is listed as non-metallic sheathed. My friend Ryan Jackson agrees with with you that it is listed based on (I)(2). In either case it is a listed assembly that is permitted for the application.
As I recall this thread is based on a conduit installation, and other than re-classification, I am not aware of any method that will permit the Class 2 cable in the same raceway as the power conductors. If you could buy the same cable as Southwire has used in the cable you linked to, it would be my opinion that you could install that in a raceway with the power conductors, but as far as I know, you can't buy that product.
 
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wwhitney

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don_resqcapt19 said:
If you could buy the same cable as Southwire has used in the cable you linked to, it would be my opinion that you could install that in a raceway with the power conductors, but as far as I know, you can't buy that product.
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But you could use #14 NM cable under 725.136(I)(1), right? Assuming the conduit fill was still in compliance.

Cheers, Wayne
 
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mstrlucky74

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don_resqcapt19 said:
That cable is permitted for that application. There are a couple of listed cables of that construction. It is my understanding that those cables are based on 725.136(I)(1) with the control cable having a jacket that is listed as non-metallic sheathed. My friend Ryan Jackson agrees with with you that it is listed based on (I)(2). In either case it is a listed assembly that is permitted for the application.
As I recall this thread is based on a conduit installation, and other than re-classification, I am not aware of any method that will permit the Class 2 cable in the same raceway as the power conductors. If you could buy the same cable as Southwire has used in the cable you linked to, it would be my opinion that you could install that in a raceway with the power conductors, but as far as I know, you can't buy that product.
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I don't think you can. I just wish someone could shed light on nay experience on large all conduit job and wiring up these fixtures. Just hard to believe you'd run two conduits to every box or fixture. Does not seem practical.

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don_resqcapt19

don_resqcapt19

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mstrlucky74 said:
I don't think you can. I just wish someone could shed light on nay experience on large all conduit job and wiring up these fixtures. Just hard to believe you'd run two conduits to every box or fixture. Does not seem practical.

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You either run two conduits or if the specs permit you run the Class 2 as exposed cable. The other choice is different equipment. There is equipment that is marked Class 1 or Class 2 and you choose which wiring method you want to use.
 
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mstrlucky74

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don_resqcapt19 said:
You either run two conduits or if the specs permit you run the Class 2 as exposed cable. The other choice is different equipment. There is equipment that is marked Class 1 or Class 2 and you choose which wiring method you want to use.
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Thanks Don. Reclassifying option doesn't seem too difficult. I think that's the easiest and least expensive option.

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wwhitney

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don_resqcapt19 said:
The other choice is different equipment. There is equipment that is marked Class 1 or Class 2 and you choose which wiring method you want to use.
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So 725.130(A) Exception 2 says that any Class 2 or Class 3 power source may be reidentified as Class 1 and the circuit run using Class 1 methods, but the equipment supplied would need to be explicitly rated for use on Class 1 circuits? The option for field reidentification only applies to the power source, not the equipment supplied?

Thanks,
Wayne
 
augie47

augie47

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don may correct me but I am of the opinion that you can run the Class 2 circuits in a cable (no conduit) to the fixture j box, maintain the required separation of power and Class 2 in that box (725.136) and install the cable discussed to the fixture again keeping the requires separation in the fixture.
 
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mstrlucky74

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Was told by engineer friend of my that inspector told him as long as the class 2 wire has 30mil insulation( he said don't quote him on that) you can run it with 120v in same conduit. I asked him which code section and still haven't heard back.
 
captaincutback

captaincutback

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Port Hueneme, CA
How Do You Re-classify?

How Do You Re-classify?

don_resqcapt19 said:
If they are not reclassified they cannot be mixed no matter what the voltage rating of the insulation is. The MC with the power and control conductors in the same cable is designed so that the control conductors comply with one of the provisions of 725.136(I) and is listed for the application.
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How do You re-classify?
 
don_resqcapt19

don_resqcapt19

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captaincutback said:
How do You re-classify?
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You take a sharpie and black out the "Class 2" marking.
725.130(A)...
Exception No. 2: Class 2 and Class 3 circuits shall be permitted to be reclassified and installed as Class 1 circuits if the Class 2 and Class 3 markings required in 725.124 are eliminated and the entire circuit is installed using the wiring methods and materials in accordance with Part II, Class 1 circuits.
Informational Note: Class 2 and Class 3 circuits reclassified and installed as Class 1 circuits are no longer Class 2 or Class 3 circuits, regardless of the continued connection to a Class 2 or Class 3 power source.
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tortuga

tortuga

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Oregon
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Electrical Design
We use 18 AWG Stranded TFFN, pulled in with power conductors in conduit:
https://www.encorewire.com/wp-content/uploads/EncoreWire-TFFN.pdf
Its rated 600V, and listed under 725.49(B)

I would prefer a label 'Class 1 system' rather than the sharpie blackout.

I would encourage you to pick obvious colors that are not used in your building.
There was a tenancy to use grey and purple which I have seen mistakenly connected to neutrals.
I spec yellow and purple.
Cheers
 
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Mustwin351

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Location
Texas
augie47 said:
don may correct me but I am of the opinion that you can run the Class 2 circuits in a cable (no conduit) to the fixture j box, maintain the required separation of power and Class 2 in that box (725.136) and install the cable discussed to the fixture again keeping the requires separation in the fixture.
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Don due you agree with Angie’s statement?

also where in 725 are the separation requirements? (don’t have my codebook on me)
 
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