PE Cable 4

[mikeydidit]

Good morning all. I have a situation on another new building that I need some advice and code and standards help with. I need to install 1 100 pair PE type cable to this new building. Most of this cable will be installed in a 4" conduit. The cable run has 1 section that is about 80’ long cable tray that is installed under a catwalk between two buildings. From the point the cable tray reaches the building, it is about 85’ to the closest point of termination. The main equipment room is located on the 5th floor. I would like to have the PE cable homerun to the 5th floor, but do to the codes (the best I understand them) 50’ is all that is allowed unless it is installed in a RGS pipe. What are my options here guy’s in order to remain within the codes and standards??

TIA for your replies.


Mike Jones
LSUHSC

 

[buitenhek]

Dear Mike,
The water block and fire hazard are your answers. Terminate within 50' of the first entry point then swing a PVC or Plenum cable (depending on environment) to the 5th floor equipment room.

Regards
Peter Buitenhek
Profit Developer.com

 

[copperfiberguru]

The 50 foot rule you refer to comes from the NEC Article 800.50 FPN No.2. You really have only two options:

1. Install metal condiut up to the 5th floor

or

2. Terminate that 100-pair at the point of entrance, add primary protection and then extend that 100-pair to the 5th floor.

However, if you do not need primary protection (see 800.30 FPN No. 2 for possible exemption) you can pull that cable directly to the 5th floor. If this is the case then the cable jacket shall be listed for the environment it passes (i.e. CMR, CMP, etc.) As always, check your local authority having jurisdiction!

I hope this helps!

Doug Bond, RCDD

 

[mikeydidit]

I appreciate your replies. The only thing is this cable will be exposed under the catwalk in an open cable tray. That being the case, I should use PE cable for this and have protection installed on it. What about the 50’ rule? This will have to come in the building at least 85’. My initial thoughts were to conduit to the first closet (again about 85') to the building entrance and terminated it there. Then run inside feed cable to the 5th floor. Any thoughts?

Mike Jones
LSUHSC

 

[Servamatic]

Mike

If you are talking about an unlisted cable, 50' unless in a rigid metal conduit system is your only option.
Generally that means the conduit should run from the outside of the building and be continuous to within 50' of your transition point to extend with a listed cable.
In most cases, the continuous system rule does not allow pull boxes that can be opened, since that is usually considered to be your point of emergence. Which means that is where the 50' rule begins.
If I read your description correctly, you would only need 40' of Rigid, and then just make sure you transition within the next 50'.
As always check with AHJ and your mileage may vary....

Richard S. Anderson, RCDD

http://www.servamatic.net

 

[mikeydidit]

Ok Richard, so you are saying that I can start my conduit from inside the building in the inside rack to the closet? Is that correct?


Mike Jones
LSUHSC

 

[franklin97355]

The first point inside the building where the cable is exposed is where your 50' starts.

 

[Servamatic]

The conduit must start outside, or as franklin said it would be exposed inside thus starting your 50'.
If the cable can be touched it is exposed.

Richard S. Anderson, RCDD

http://www.servamatic.net

 

[mikeydidit]

I think that you have me on the right tract now guy's. Thank you all as always fro your help.

Mike Jones
LSUHSC