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    #16
    Originally posted by mstrlucky74 View Post
    But the Lutron equipment that's feeding the fixtures are rated class 2
    Buy a brand that works for your installation, or wire the Class 2 equipment per the code rules.
    Don, Illinois
    (All code citations are 2017 unless otherwise noted)

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      #17
      Originally posted by don_resqcapt19 View Post
      The code permits them to be in the same box for the connections to the equipment. The code does not permit them to be in the same raceway or cable.
      Reclassification just means you remove or cover all the Class 2 markings and wire the controls using a Chapter 3 wiring method. In that case, the control wiring must follow the same rules as the power wiring.
      That makes sense. Thank you.
      If Billy Idol is on your playlist go reevaluate your life.

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        #18
        Originally posted by ActionDave View Post
        All the 0-10V controlled lights I have wired up have the power conductors and dimming conductors going to the same make up box on the fixture and the dimmers have no way to separate the power and dimming wires in the junction box for the switch, so are they by default "re-classifiable"?

        What does it even mean to re-classify a class 2 power supply or system?
        Not sure what you mean. You can have two separate conduits(power & 0-10v) going to same box.

        Comment


          #19
          Originally posted by mstrlucky74 View Post
          Thanks. Which code section does it not allow to mix these even is same insulation?
          Basically the general requirements for a class 2 circuit.

          The rule isn't so much "same insulation" as it is "rated for the maximum voltage applied to any of the conductors". You can have 300 and 600 volt insulation in same raceway if none of those conductors is used for more than 300 volts.


          I am not all up to speed on what is all out there for low volt lighting control/dimming, but similar situations have been around for a long time with HVAC controls.

          If you want to run the 24 volt control conductors in same raceway with power wiring - it usually needed to be the raceway containing the power wiring to that HVAC equipment and not just any raceway with power wiring in it. You then needed to use conductors rated for maximum voltage present in the raceway. Then you must make it so the class 2 source is no longer identified as a class 2 source. Along with that goes making all of the control circuit comply with rules for a class 1 circuit - meaning you will use a line voltage thermostat instead of one intended for use only on class 2 circuits. You can not run half the circuit within power raceway because it is convenient then transition to CL 2 cable and run the other half the circuit to a typical CL2 thermostat, or other CL2 only system devices.
          I live for today, I'm just a day behind.

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            #20
            Originally posted by kwired View Post
            Basically the general requirements for a class 2 circuit.

            The rule isn't so much "same insulation" as it is "rated for the maximum voltage applied to any of the conductors". You can have 300 and 600 volt insulation in same raceway if none of those conductors is used for more than 300 volts.


            I am not all up to speed on what is all out there for low volt lighting control/dimming, but similar situations have been around for a long time with HVAC controls.

            If you want to run the 24 volt control conductors in same raceway with power wiring - it usually needed to be the raceway containing the power wiring to that HVAC equipment and not just any raceway with power wiring in it. You then needed to use conductors rated for maximum voltage present in the raceway. Then you must make it so the class 2 source is no longer identified as a class 2 source. Along with that goes making all of the control circuit comply with rules for a class 1 circuit - meaning you will use a line voltage thermostat instead of one intended for use only on class 2 circuits. You can not run half the circuit within power raceway because it is convenient then transition to CL 2 cable and run the other half the circuit to a typical CL2 thermostat, or other CL2 only system devices.
            So can't run the 0-10v dimming wires with 120v power if the dimming wires are 600v insulation?

            Comment


              #21
              Originally posted by mstrlucky74 View Post
              So can't run the 0-10v dimming wires with 120v power if the dimming wires are 600v insulation?
              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.
              Don, Illinois
              (All code citations are 2017 unless otherwise noted)

              Comment


                #22
                Originally posted by don_resqcapt19 View Post
                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.
                Unless you re classify it, right?
                If Billy Idol is on your playlist go reevaluate your life.

                Comment


                  #23
                  Originally posted by ActionDave View Post
                  Unless you re classify it, right?
                  If you reclassify it, it is no longer a Class 2 circuit. When you do that you must run 100% of the circuit using a Chapter 3 wiring method, not just the part that is run with the power conductors.
                  Don, Illinois
                  (All code citations are 2017 unless otherwise noted)

                  Comment


                    #24
                    Originally posted by don_resqcapt19 View Post
                    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.
                    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.
                    Last edited by mstrlucky74; 04-13-19, 08:20 PM.

                    Comment


                      #25
                      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/s...4089400350.pdf
                      At my age, I'm accustomed to restaurants asking me to pay in advance, but now my bank has started sending me their calendar one month at a time.

                      Comment


                        #26
                        Originally posted by augie47 View Post
                        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/s...4089400350.pdf
                        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.
                        Don, Illinois
                        (All code citations are 2017 unless otherwise noted)

                        Comment


                          #27
                          Originally posted by don_resqcapt19 View Post
                          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.
                          But you could use #14 NM cable under 725.136(I)(1), right? Assuming the conduit fill was still in compliance.

                          Cheers, Wayne

                          Comment


                            #28
                            Originally posted by wwhitney View Post
                            But you could use #14 NM cable under 725.136(I)(1), right? Assuming the conduit fill was still in compliance.

                            Cheers, Wayne
                            That would comply with the code. You could use the NM for either the power or control and be in compliance.
                            Don, Illinois
                            (All code citations are 2017 unless otherwise noted)

                            Comment


                              #29
                              Originally posted by don_resqcapt19 View Post
                              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.
                              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.

                              Sent from my SM-N960U using Tapatalk

                              Comment


                                #30
                                Originally posted by mstrlucky74 View Post
                                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.

                                Sent from my SM-N960U using Tapatalk
                                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.
                                Don, Illinois
                                (All code citations are 2017 unless otherwise noted)

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