What is the code for sealing low voltage?

[ksilv@atseagle.com]

Interesting forum. New member.

I am a sales engineer for a tel/data company and all we do is install low voltage (voice/data/video/audio) cabling.

The posts about low voltage are interesting and, separate from this, if anyone has questions about datacom wiring, I'll be happy to field them (to my best ability!!) here or via e-mail.

The question I have is in regard to sealing of conduit for low voltage installations. We are being told by a customer that conduit we used for low voltage cable needs to be sealed in certain areas as he has some areas which require explosion proof devices. I understand what the sealing is for but my question is when are you required to seal conduits at various intervals and do those codes also apply to the non hazardous areas where conduit and low voltage is installed?

If I have not provided enough information in the above text, feel free to let me know.

Thanks in advance,

Kevin

 

[hbiss]

Re: What is the code for sealing low voltage?

We are being told by a customer that conduit we used for low voltage cable needs to be sealed in certain areas as he has some areas which require explosion proof devices.

Probably, but it can be a lot more involved than that. What is the classification of these "certain areas", or what is going on there that requires explosion proof devices? What equipment are you installing in these areas?

I can tell you that conduit installed in non-classified areas has no sealing requirement.

-Hal

 

[ksilv@atseagle.com]

Re: What is the code for sealing low voltage?

Thanks Hal... been reading a lot of your posts!!

I am working on getting the exacts, but generally speaking it is a HUGE manufacturing plant and there is one (very small) area which we ran paging speakers with the cable in conduit which is either Class 1 or Clss 2 hazardous. I think there is one, maybe two speakers in this area.

My assumption (I said it!!) is that the only area where sealing applies is the haz area....

I am going to meet with them tomorrow and expect to have far more detail to add.

Kevin

 

[chrsb]

Re: What is the code for sealing low voltage?

I just did a Class 2 instalation and we had to put seal off's on every conduit right as it left the room. The interval was right after the conduit left the room. This was at a elementary school in a storage room where they stored the lawnmowers and snow blowers.

 

[hbiss]

Re: What is the code for sealing low voltage?

What kind of speakers did you use? The speakers would have to be explosion proof. Conduit would have to be RMC. Not sure if you would be allowed to install any of this unless you were an EC.

-Hal

 

[chrsb]

Re: What is the code for sealing low voltage?

Sorry, it was lights I put in. I couldn't belive these things, 2k each. I am a EC so it was no problem. We did run RMC to the lights. I guess it would be the same for speakers, some sort of encloseur. I would check out Hubbles site to see if they have anything. Sorry for the confusion, it didn't hit me you were asking about speakers.

 

[hbiss]

Re: What is the code for sealing low voltage?

No, Hubbell wouldn't have anything in the way of speakers. Atlas Sound is one of the most common manufacturers. All that is available in explosion proof are horn type speakers and of course they are big bucks.

-Hal

 

[ksilv@atseagle.com]

Re: What is the code for sealing low voltage?

Gotcha -

Well, I am now being told two things. My installers are telling me we did not run cable in this are, the customer is telling me we have unsealed conduit.

I can understand the requirement for rigid and sealing in suchan environment but I would sub that out to an EC as we do not perform that work.

The answer to my question is clear from what Hal is saying and here is my interpretation...

If you are working in a Class 1 or 2 area, you need to enter and exit with rigid, seal upon entrance and exit, and install EP devices.

I think I am going to end up finding out that the customer told our sales person one thing (no haz areas) and is now trying to get something for nothing.

Time for a site visit....

Thanks again!!

Kevin

 

[hbiss]

Re: What is the code for sealing low voltage?

Kevin, find out what goes on in this area and post in the Hazardous(Classifed)Locations forum. Same guys but sometimes your question gets noticed faster by those members who are more familiar with this. They can give you in depth requirements.

-Hal