Article 645 - Type SJ Cable under raised floor

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spsnyder

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Is SJ cable flexible cable allowed under a raised floor utilizing Article 645? I say no. Here's where I think I am obligated to...

"Article 645 Information Technology Equipment

645.5 Supply Circuits and Interconnecting Cables

(D) Under Raised Floors

(5) Cables, other than those covered in (D)(2) and those complying with (D)(5)(a), (D)(5)(b), or (D)(5)(c), shall be listed as Type DP cable having adequate fire-resistant characteristics suitable for use under raised floors of an information technology equipment room."

The SJ flexible cord runs from the receptacles under the raised floor to the IT equipment. I looked for type DP cable on the internet and didn't have any luck. Is this type cable common? Thanks.
 
First of all make sure that article 645 applies. In order to use article 645 all of the requirements of 645.2 must be met. Very few "computer rooms" meet these requirements unless they are built specifically to these specifications. Otherwise the area under a raised floor is usually an air-handling space and the requirement in 300.22(C) must be met.
 
haskindm - Good point on the requirements 645. It is a new building and was designed to be a server room from the get-go, but I will verify.

As far as 300.22 (C) is concerned the next paragraph usurps the requirements assuming it falls under 645.

"300.22 (D) Information Technology Equipment Electric wiring in air-handling areas beneath raised floors for information technology equipment shall be permitted in accordance with Article 645."


Dennis. IMO Flexible cords are allowed under raised floor in this case per

"400.7 (6) Connection of utilization equipment to facilitate frequent interchange "

However IMO it has to be type DP. Has anyone come accross Type DP, fire resistant cable? Thanks.
 
Yes but 400.8 (5) Not permitted where concealed by walls, floors, etc. Art. 645(D) (5) seems to indicate the cable must be a DP cable -- whatever that is--- to be installed under the floor.
 
Thank you all for your help. That's the same conclusion I came to, but seemed weird that I can't find any Type DP cable. The IT people brought the equipment into the room, so I am going to work through them. Will let you know what I find regarding DP cable.

Regards
 
Thank you Ron and Pierre. I feel a lot better that there are in fact many manufacturers of required equipment. Regards. More importantly Ron, that webpage is a great future resourse. I never thought to go through UL to find manufacturers of equipment meeting UL requirements.
 
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It will be very interesting to hear the result of the NFPA balloting of the 2008 NEC, as there are significant changes that are possible for this topic 645.5(D).

The answer to these questions may be different in the next code cycle.
 
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