Hi, new member and first post, not sure if I am posting in the right category. The company I work for does service work at retail gas stations. One of the tasks we perform on a routine basis is to replace the gas dispensers with new models. The challenge we come up against quite frequently at older stations there is only on conduit to the gas dispenser. A modern gas dispenser needs three circuit types, a class 1 for the power, a class 2 or 3 for the intercom, and a communications circuit in the form cat 5 cable rated for a hazardous location. My question has to do with combing all three circuit types into one conduit. I think it can be done, can someone confirm? Here is why I think it can be done:
The class 2/3 circuit can be reclassified and combined in a raceway with a class 1 circuit per 725.130 as long as you remove the circuit class markings of the equipment per 725.124. The one I am struggling with is the communications circuit (it is not a POE circuit, just a plain old data cable). The best I can come up with is exception #3 of 800.133 which leads you to 620.36. To me this says you can do it as long as your communications wire is rated the same as your class 1 wire. Where I am doubting this is that section 620 deals with Elevators, Dumbwaiters, Escalators, Moving Walks, Platform Lifts, and Stairway Chairlifts. So what takes precedence? The fact that code exists that allows for the combining of comm. & class 1 or the equipment listed in the title of 620.
Any guidance would be greatly appreciated.
All code references from 2014 edition.
725.130 Wiring Methods and Materials on Load Side of the Class 2 or Class 3 Power Source. Class 2 and Class 3 circuits on the load side of the power source shall be permitted to be installed using wiring methods and materials in accordance with either 725.130(A) or (B).
(A) Class 1 Wiring Methods and Materials. Installation shall be in accordance with 725.46.
Exception No. 1: The ampacity adjustment factors given in 310.15(B)(3)(a) shall not apply.
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.
620.36 Different Systems in One Raceway or Traveling Cable. Optical fiber cables and conductors for operating devices, operation and motion control, power, signaling, fire alarm, lighting, heating, and air-conditioning circuits of1000 volts or less shall be permitted to be run in the same traveling cable or raceway system if all conductors are insulated for the maximum voltage applied to any conductor within the cables or raceway system and if all live parts of the equipment are insulated from ground for this maximum voltage. Such a traveling cable or raceway shall also be permitted to include shielded conductors and/or one or more coaxial cables if such conductors are insulated for the maximum voltage applied to any conductor within the cable or raceway system. Conductors shall be permitted to be covered with suitable shielding for telephone, audio, video, or higher frequency communications circuits.
Your typical electrical contractor would have a steep learning curve on this type of work and we are not paying them to learn. The electrical contractors that we use we have either trained by us or they are our competition.
The problem is the AHJ at the State level. What we get from them is “it is not allowed because we said so”. I have asked them multiple times for a code citation as to why it is a violation and have yet to get an answer.
And yes of course there are permits required for this type of work. 2 from the State and sometimes a redundant local permit. The local permit is usually only required if the local municipality uses a third party as their BCO and inspection company. We have been doing this type of work for close to 40 years and are not looking to cut corners, just to be able to do what appears to be allowed by code. Can you address my code specific questions.
And you come to a Home Inspector message board to learn ?
Hmmm…I would visit www.MikeHolt.com and ask your question before I would ask here. While their are many highly trained HI’s here and a spattering of Electrical Experts…not sure I would be asking that type of question on this forum…just sayin.
However…with that said the weaker side of my “helping spirit” will answer the jist of your question.
The major issue you face is not that the NEC permits you to “reclassify” Class 2/3 circuits as Class 1 circuits, which are no longer Class 2/3 circuits anymore and may cause a problem with your equipment termination where it demands class 2/3 conductors to be used…Since they are now no longer Class 2 or 3 conductors.
The other issue is on the data cables you speak off as changes are their insulation is not in accordance with Part II of 725 either. However, if you are classifying the Cat 5 as communication then you may want to check out 800.133(A) and remember in your plan you “reclassified” your previously Class 2 or 3 conductors as now Class 1…then Article 800 presents a problem for you.
But alas…quick analysis and not alot of thought into it…I would again post on a forum like Mike Holts of others where they have time to ponder all your options.
ALSO this might be helpful to you…Notice the communication and power are in separate raceways…
When doing some Google searches on the subject, there was a related post on this board, that is how I ended up here. Besides, just because you are a home inspector doesn’t mean you don’t know NEC or also do commercial inspections. I definitely appreciate your help, especially the milkholt one. I have received some good responses there already.
Section 622.36 doesn’t declassify the comm cable, it just says its insulation must be rated per the highest conductor in the conduit and some ground requirements. Which in this case would be 120V. It doesn’t even say the wiring methods must be in accordance with the other circuits.
622.36 is very confusing to me since it in a way contradicts (contradicts is to harsh a word, maybe ‘is not as strict as’ would be better) what NEC says about combining different circuit types in other sections. Section 725 for instance is very well thought out.
You are most welcome…I am not sure where you are getting Article 622…but the question would be…is it germane to your install and changes are it is not.
The problem with the communication cables in Article 800 as I stated is very real and the re-identification of the class 2/3 to class 1 will create a problem for you also as stated.
lastly, I am not bashing you my friend on the post here but more giving you some direction on where to best get your answers in the quickest amount of time. As for me…well I am no longer a Home Inspector and kinda dabble in the NEC just a little…but only a little…
Good luck on your quest…I would place the Class 2/3 re-identified if the equipment permits in with the power source and a separate raceway for the communication circuits (data, etc.) but thats me…I like to keep it simple.
