conduits to cable tray

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Yup. There's a fitting for that. I forget the name of it, but I have a picture of it in my head. I am unable to link to my head at this time.
 
Here's a few catalog examples of the fitting I was thinking of. I think that there are other ways to bond the leaving raceway as well, besides using this type of fitting, but this is a good choice:

conduittocabletray.jpg
 
ftn117 said:
should conduits be bonded to the cable try that the conducters leave and lay in the try?
thanks
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Don't forget to install a cable gland at the end of the conduit, so the conduit system is CLOSED as per the Code and the cable is secured at the point of entry. Unless of course the conduit run is open at both ends, in which case it is no longer used as a conduit, but a cable support system. In the later case you would only need pop-on bushings to protect against abrasion at the entry point. Note that the conduit is not tested and approved for this purpose, but it is routinely used as such.

Make sure that the conduit clamp is approved as it is part of the current carying grounding path besides of having a mechanical support function.
 
weressl said:
Don't forget to install a cable gland at the end of the conduit, so the conduit system is CLOSED as per the Code and the cable is secured at the point of entry.
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Hmm... interesting point. In all the industrial installations I have taken part in, I can't recall anyone, including myself, having used a gland (...or glands for multiple cables?) at the tray end.
 
weressl said:
...I was not aware, nor do I think, that its is an actual acronym.
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A lot of our working slang terminology originated from catalog model nos. or even manufacturer names. Take for example "minis" for both Mineralac and non-Mineralac pipe hangars, or "Madison straps" for old work box mounting

So what is the criteria for an acronym to qualify as an "actual acronym"???

Regardless, it doesn't matter whether it's an actual acronym or not, you'd appear somewhat ignorant if you didn't know what a CGB is in an installation environment.
 
weressl said:
Don't forget to install a cable gland at the end of the conduit, so the conduit system is CLOSED as per the Code and the cable is secured at the point of entry. Unless of course the conduit run is open at both ends, in which case it is no longer used as a conduit, but a cable support system. In the later case you would only need pop-on bushings to protect against abrasion at the entry point. Note that the conduit is not tested and approved for this purpose, but it is routinely used as such.

Make sure that the conduit clamp is approved as it is part of the current carying grounding path besides of having a mechanical support function.
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I was not aware the NEC requires a CGB (cable-gland) every time a conduit attaches to a Tray... have I missed it?
 
stickelec said:
I was not aware the NEC requires a CGB (cable-gland) every time a conduit attaches to a Tray... have I missed it?
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The point has nothing to do with the conduit and tray, it has to do with a cable entering a conduit system and terminating. There are two points
1./ Securing the cable at the point of entry. When you run a Romex into a box, you secure it a point of entry. This is primarily done for stress relief, so if there is mechanical pull on the cable it is relevied by the mechanical termination, not by the electrical termination of the conductor.(The stress on the conductor termination can cause it to loosen and strart a hot spot.
2./ Whenever you make a point of entry into a closed system you must maintain its environmental integrity, eg. NEMA1, NEMA3, NEMA4, etc. If this is an outdoor installation then it should be NEMA 3 or 4 or similar.
 
If there was a dozen Type-TC cables in the CGB, I'm not sure the NEMA-4 "rating" could be maintained without putting too much crush on the cables.
 
weressl said:
CGB is not suitable or approved for multiple cables, only for single cables.
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I believe you are in error (if you are referring to CGB, in the generic sense). The following is only one example...

 
They're perfect for a Bulkhead, and/or if they are in the Engineers Spec., but otherwise I would not attempt to try to justify the cost (T&M) to simply close a conduit landing on a Tray. Unless of course it is required by code... which I can't find.
 
weressl said:
See attached document.
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Nothing better to do today? :wink:

Jeering aside, your document appears quite comprehensive... and I'd like to go on record as being in agreement with you. I just find it amazing that this requirement has and most likely will continue to be, at large, neither practiced nor enforced.
 
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Smart $ said:
Some people refer to them as CGB's (Cable Gland [or Grip] Body).

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this picture is a cable connector for individual tray conductors (multi cable) for termination to a jbox or cabinate from tray

I was under the impression, perhaps wrongly, that you were talking about a pipe that comes from a panel then terminates to tray allowing conductors to go on their merry way on the tray system till they get picked up by another pipe that starts at the tray and termiantes at a dissconnect or a control cabinate in a non hazardous atmosphere
 
weressl said:
See attached document.
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That is a very well prepared document and something that would be of real benefit in a Engineering Spec. But... I honestly cannot find were it is required to use a Sealing Bushing on conduit that is attached to a Cable Tray.

As mentioned by Tori, we are not talking about enclosures. The best I can dig out of the 2005 NEC Art 300 and 392 is that an Insulated Bushing is all that is required.

I'm not trying to be argumentive, just trying to learn if I have been wrong all these years. Please point to the exact ref in the NEC that shows the requirement. Thanks
 
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