I used a UL rated 600V SO stiff Cord (Yellow) to run 24 VDC discrete alarms (Not Fire alarms) Using "C" clamps and running the cord along the wall. I was told by an inspector that this was against NEC 400.8 Code. I did not think NEC codes applied to 24 VDC Signal conductors. Is this true. Did I break code?

 

You should have asked him what would make him happy. Inspectors have a great deal of latitude in their interpretation and enough things are not specified where what is OK to one is not to another. If he wants to be difficult, you won't win this argument regardless of what the NEC says. Could be the color, could be the mounting, could be confusion with a power circuit, using "portable" cordage without protection, almost anything. They generally love to be asked and it's a good idea to play nice unless you want to do a lot of rework.

Regards
cww

 

400.8 details where and when you are allowed to use these kind of cords. If the application is not listed there, you can't use it.

It would probably be OK if you did the same exact installation using a chapter 3 wiring method such as tray cable.

It is an idiotic restriction IMO, but the inspector is probably correct, unless you can shoehorn this particular install into one of the exceptions in 400.8.

 

At the end of the code, it basically says...."And whatever else the local permitting authority wants", so you can't really challenge it by force. Most of them will reason with you, and if you can show them that your installation is in fact per the letter of the law, they're usually OK with that, but bottom line is that they can demand anything they want.

 

Most inspectors will not allow SO cords for 'permanent installations' unless it has a plug connection. Strapping it to a wall, framing members, etc. is a red flag to them. You need to either run conduit or flexible conduit to your equipment, unless the cabling has been included as part of your UL listed assembly.

 

...."And whatever else the local permitting authority wants"

That is just plain false. The only authority the local inspector has is what authority he is given under state or local laws.

That does not mean that they are never going to make mistakes in what they think is in the code, but they have zero authority to make it up as they go. They all have bosses that you can appeal to if they get out of line.

Now in practice, there are some of them that are just plain control freaks who don't really understand the codes they are enforcing, and those guys can be really painful to deal with.

I don't think that is what the original poster is running into though. He appears to have made an install that is not in compliance with the code. That's not the inspector's fault.

--
Bob

 

There is a statement in the code giving the permitting jurisdiction overriding authority, though they will usually back down if you read them chapter and verse in the code.

If I have a chance, I'll go back and try and find the explicit wording in the Code.

 

90.4 of the NEC is often used as a "I can demand anything I want" by many inspectors, but as bob mentioned, they are dead wrong and most of them know it. Yes, local inspectors can interpret the rules, and specifying decisions that are stated in the code as "up to the AHJ", but they can't make them up on the spot.

Any rule or requirement not found in the NEC (if adopted) must be in writing, by local law or ordinance.

For me, seeing 90.4 on an inspection report screams "inferiority complex" and ends up with a phone call to the boss. Yes, you choose your battles, but it usually takes one battle to show the inspector you will not be treated like a little kid to be the inspector's puppet.


For reference, part of 90.4 (section 90 itself is unenforceable, it is informative only) states "The authority having jurisdiction for enforcement of the Code has the responsibility for making interpretations of the rules, for deciding on the approval of equipment and materials, and for granting the special permission contemplated in a number of the rules."

 

It only takes one battle with an inspector to waste lots of time with petty BS as time goes on. Even if you win, you lose.

Regards
cww

 

Take a look at 720.11. It requires cables supplying circuits of less than 50 volts to be installed in a manner that is consistent with standard industry practice. So it appears that you are violating the code.