ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
Baseboard Mounted Light Bulb Socket
by SPSchuman. 07/15/19 03:22 PM
Hunter Fan Recalls Brunswick 3 & 4 Light Fans
by Admin. 07/11/19 11:08 AM
Honeywell Recalls some Smoke Sensors
by Admin. 07/11/19 11:03 AM
New in the Gallery:
What is this for?
Plug terminals
Who's Online Now
1 registered members (crselectric), 8 guests, and 11 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 3 1 2 3
Receptacles under raised floors #92113
02/26/05 02:59 PM
02/26/05 02:59 PM
E
Elzappr  Offline OP
Member
Joined: Dec 2001
Posts: 270
Oregon
Can receptacle outlets be placed under raised floors for power to office equipment?

2017 / 2014 NEC & Related Books and Study Guides
Re: Receptacles under raised floors #92114
02/26/05 05:15 PM
02/26/05 05:15 PM
G
George Little  Offline
Member
Joined: Jan 2004
Posts: 1,498
Michigan USA
I would say probably it's red tag time. I say that because a receptacle under the floor would obviously leed to a cord under the floor and now we have trouble with 400.8(5). The exception could be in a computer room, raised floor.


George Little
Re: Receptacles under raised floors #92115
02/26/05 08:03 PM
02/26/05 08:03 PM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,373
Estero,Fl,usa
Even under a computer room raised floor you need plenum rated power cords. There are always going to be receptacles but they will be IEC309s or Russell Stolls, not the usual NEMA 5-15


Greg Fretwell
Re: Receptacles under raised floors #92116
02/26/05 08:36 PM
02/26/05 08:36 PM
R
Ron  Offline
Member
Joined: Mar 2002
Posts: 582
White Plains, NY
Since a flexible cord can't be below the raised floor, there is no need for a receptacle.
If you are 645 compliant, then its ok if the cord is rated as 'DP'.
Why not place a floor box in the raised floor tile, then all is ok.


Ron
Re: Receptacles under raised floors #92117
02/26/05 10:33 PM
02/26/05 10:33 PM
E
Elzappr  Offline OP
Member
Joined: Dec 2001
Posts: 270
Oregon
You all have confirmed my suspicions. What I am dealing with is a 5 story building with cords plugged in regular duplex receptacles under the raised floors. The cords are actually 20' long plug strips. they poke up through bushed holes in the concrete floor tiles. This is not a computer room nor server room situation, just a general office space.
As far as I know, this set-up has never been allowed by code. Right?

Re: Receptacles under raised floors #92118
02/26/05 10:55 PM
02/26/05 10:55 PM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,373
Estero,Fl,usa
That is not legal, nor is simply converting old computer room space to office space, retaining the raised floor for a "convienient" wiring bay. When computers stopped being an acre of boxes and became a rack they had lots of raised floor real estate. It ends up being an office but they still use the floor for a plenum and they lose all the breaks they got in 645.


Greg Fretwell
Re: Receptacles under raised floors #92119
02/27/05 01:39 AM
02/27/05 01:39 AM
G
George Little  Offline
Member
Joined: Jan 2004
Posts: 1,498
Michigan USA
Greg, are you sure about this?
Quote
Even under a computer room raised floor you need plenum rated power cords. There are always going to be receptacles but they will be IEC309s or Russell Stolls, not the usual NEMA 5-15

I thought that the cord and the wiring method to the receptacle were the only issues. please educate me.


George Little
Re: Receptacles under raised floors #92120
02/27/05 01:59 AM
02/27/05 01:59 AM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,373
Estero,Fl,usa
Actually Ron hit the code issue. (listed "DP" cable)
The reason you don't see regular receptacles under the floor is you don't want to crash the system because someone yanked the wrong cable and pulls out a plug to a critical box.


Greg Fretwell
Re: Receptacles under raised floors #92121
02/27/05 02:47 AM
02/27/05 02:47 AM
G
George  Offline
Member
Joined: Feb 2002
Posts: 375
I don't wish to start a fight over the issue, but I don't think it is as clear cut as it could be ...

I can certainly run a standard cord under a table. I can carpet my floor with tables. I can place the recept below table ehight. I can walk on top of the tables and place my furniture on top of the tables.

I used the word "table" where most people would use the word "floor."

Re: Receptacles under raised floors #92122
02/27/05 03:44 AM
02/27/05 03:44 AM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,373
Estero,Fl,usa
I can call my pool a bathtub but that doesn't mean the AHJ will let me ignore 680.
If your AHJ decides your tables are really a floor you will have to follow the rules about penetrations.
Virtually all computer room floors are plenums, moving environmental air. That is why they have the rules about cable flamability.
There are also recognized office floor duct systems so we want to be sure what we are talking about here.


Greg Fretwell
Page 1 of 3 1 2 3

Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
Posts: 362
Joined: April 2003
Show All Member Profiles 
Top Posters(30 Days)
Admin 5
Popular Topics(Views)
256,968 Are you busy
192,848 Re: Forum
182,467 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.029s Queries: 15 (0.004s) Memory: 1.0262 MB (Peak: 1.2032 MB) Zlib enabled. Server Time: 2019-07-16 08:17:25 UTC