Provided that all the requirements of 645-2 are met, does Art 645 allow for non-plenum cord & plug from IT equipment to under raised floor receptacle (plenum space)? Although 645-5b approves the use of cord & plug, & 645-5d addresses the branch circuit requirements to the underfloor receptacle, it seems to only address the use of data cabling for under raised floor. Can you clarify this?
Art. 645 UF cord & plug
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ron
Senior Member
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- New York, 40.7514,-73.9925
Re: Art. 645 UF cord & plug
The cord installed below the raised floor must be "DP" rated per 645.5(D)(5). Essentially none are, so you can't place the cord below the floor.
The cord installed below the raised floor must be "DP" rated per 645.5(D)(5). Essentially none are, so you can't place the cord below the floor.
Re: Art. 645 UF cord & plug
That was what my thoughts were until I tried to figure out what a Type DP cable was, as I couldn't see it listed anywhere in the NEC. I found a UL sheet on the internet and it appears DP stands for data processing cable. So it seems that 645-5d5 address data cables only (and some of the cables listed are not plenum rated)
http://ulstandardsinfonet.ul.com/scopes/1690.html
That was what my thoughts were until I tried to figure out what a Type DP cable was, as I couldn't see it listed anywhere in the NEC. I found a UL sheet on the internet and it appears DP stands for data processing cable. So it seems that 645-5d5 address data cables only (and some of the cables listed are not plenum rated)
http://ulstandardsinfonet.ul.com/scopes/1690.html
ron
Senior Member
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- New York, 40.7514,-73.9925
Re: Art. 645 UF cord & plug
DP rating is the outer sheath of a cable, traditionally for the power to data processing equipment, hence the name, DP.
It is a outer jacket type only identified by UL standards and required only by the NEC in 645.
DP rating is the outer sheath of a cable, traditionally for the power to data processing equipment, hence the name, DP.
It is a outer jacket type only identified by UL standards and required only by the NEC in 645.
ryan_618
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- Salt Lake City, Utah
Re: Art. 645 UF cord & plug
I don't understand why they would have to be DP rated.
The concept of allowing non-plenum rated cables in the IT room is that it has its own air handling system, and the room is not occupied by persons. Why wouldn't the code permit this?
I don't understand why they would have to be DP rated.
The concept of allowing non-plenum rated cables in the IT room is that it has its own air handling system, and the room is not occupied by persons. Why wouldn't the code permit this?
ron
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- New York, 40.7514,-73.9925
Re: Art. 645 UF cord & plug
There was a proposal made at least the last code cycle, if not several cycles to relax or eliminate that requirement.
There was a proposal made at least the last code cycle, if not several cycles to relax or eliminate that requirement.
ron
Senior Member
- Location
- New York, 40.7514,-73.9925
Re: Art. 645 UF cord & plug
If I recall, the reason the proposals were shot down, was the possible fire load below the raised floor may be higher without the special cable. But as pointed out, they let non-plenum rated comm cables below the floor, they require smoke detection below the floor, it's an isolated HVAC system, so it just doesn't make sense to use the fire load argument.
I also believe that rather than discuss the proposal, they referred it to NFPA 90, which also doesn't make sense since why would NFPA 90 have any control of text in the NEC?
If I recall, the reason the proposals were shot down, was the possible fire load below the raised floor may be higher without the special cable. But as pointed out, they let non-plenum rated comm cables below the floor, they require smoke detection below the floor, it's an isolated HVAC system, so it just doesn't make sense to use the fire load argument.
I also believe that rather than discuss the proposal, they referred it to NFPA 90, which also doesn't make sense since why would NFPA 90 have any control of text in the NEC?
sandsnow
Senior Member
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- Southern California
Re: Art. 645 UF cord & plug
Here is a piece of Type DP cable. It was in a Info. Tech. Room. Sorry about the glare.
Here is a piece of Type DP cable. It was in a Info. Tech. Room. Sorry about the glare.
ron
Senior Member
- Location
- New York, 40.7514,-73.9925
Re: Art. 645 UF cord & plug
Larry,
Excellent find. My understanding from speaking with many of the manufacturers, was that they didn't have a DP rating on their cables.
Do you happen to remember the manufacturer of the equipment that was connected to?
Larry,
Excellent find. My understanding from speaking with many of the manufacturers, was that they didn't have a DP rating on their cables.
Do you happen to remember the manufacturer of the equipment that was connected to?
sandsnow
Senior Member
- Location
- Southern California
Re: Art. 645 UF cord & plug
Ron
www.apc.com is the manufacturer of the PDU.
www.lappusa.com is the manufacturer of the cable.
EMRB is the UL category for data processing cable.
I hope that helps
Ron
www.apc.com is the manufacturer of the PDU.
www.lappusa.com is the manufacturer of the cable.
EMRB is the UL category for data processing cable.
I hope that helps
kevinware
Senior Member
- Location
- Louisville, KY
Re: Art. 645 UF cord & plug
ron
Senior Member
- Location
- New York, 40.7514,-73.9925
Re: Art. 645 UF cord & plug
Kevin,
It seems that the link you provided is for the branch circuit supply conductors in raceway covered by 645.5(D)(2)
The "DP" rated conductors per 645.5(D)(5) do not include the branch circuit supply conductors. The DP cables covered by 645.5(D)(5) are typically the cord and cap from the power strip to the receptacle.
Kevin,
It seems that the link you provided is for the branch circuit supply conductors in raceway covered by 645.5(D)(2)
The "DP" rated conductors per 645.5(D)(5) do not include the branch circuit supply conductors. The DP cables covered by 645.5(D)(5) are typically the cord and cap from the power strip to the receptacle.
kevinware
Senior Member
- Location
- Louisville, KY
Re: Art. 645 UF cord & plug
Thanks for the correction Ron. So if I am understanding 645.5(D)(5) correctly then the power strips that are installed in some of our network racks are in violation of this article. The power strips Tripp-lite are tie wrapped into the racks and the cord and cap is feed through the cut-out in the floor tile and plugged into my branch circuit. Am I correct that this is a violation??
Thanks for the correction Ron. So if I am understanding 645.5(D)(5) correctly then the power strips that are installed in some of our network racks are in violation of this article. The power strips Tripp-lite are tie wrapped into the racks and the cord and cap is feed through the cut-out in the floor tile and plugged into my branch circuit. Am I correct that this is a violation??
ron
Senior Member
- Location
- New York, 40.7514,-73.9925
Re: Art. 645 UF cord & plug
Per the last few code cycles, that cord from the power strip needs to be DP rated (like in the picture from Larry).
Per the last few code cycles, that cord from the power strip needs to be DP rated (like in the picture from Larry).
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