Do Power Strips violate the NEC? 1

[mmdgatech]

I am working on a project where the owner would like to use a power strip that has a local occupancy sensor as a means to shut off power at each work station. The occupancy sensor permanently mounts to the station and is attached directly to the outlet strip.

However, I am concerned that the use of power strips as a permanent installation is a violation of the NEC but I can not seem to find anything in the code that address these.

Does anyone know if the NEC address this situation? Are power strips considered 'extension cords'? Anyone else ever run into this situation?

Thanks for you help.
mmdgatech

 

[itsmoked]

The fact that they have circuit breakers in them which prevents the 'add another zip cord get 2 more outlets', until something starts to smoke syndrome. I think this avoids the extension cord blues. I mean every computer station has one! The one I'm tying this on has 4 powerstrips!! And no! I am not giving up my Lava Lamp!

But someone may come by with a definitive answer.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[electricpete]

My wife always gives me grief because she thinks the education of an EE should be good enough to enable him to figure out how to make wires tidy (if good for nothing else).

Now I don't feel so bad (4 POWER STIPS!?)

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[itsmoked]

Yes..

Projector Lamp (for lighting desk)
Monitor (LCD)
Monitor (CRT)
Speaker (#1 Advent with internal 120Vac amp)
Speaker (#2 Advent with internal 120Vac amp)
Sub Woofer (Creative Labs with internal 120Vac amp)
Mouse Charger
Phone
TV (7" Sony)
WFI Router
Wired Router
Ink jet
Ink Jet (11x17)
Flat plate scanner
Fax machine
PC (main)
PC (old Win98 for non supported apps)
Call processor
USB drive #1 (250G)
USB drive #2 (250G)
USB drive #3 (300G)
Keyboard switch
Shredder
UPS
SLAM modem
Flashlight (rechargeable, Streamlight, Stinger HP, [highly recommended])
DUT (Device Under Test needing a Wall-wart - temp)

And of course since this is California:
Lava Lamp. (Red blobs / clearish liquid)

Twenty eight plugs that need a home..

During my survey I discovered another powerstrip so I actually have FIVE!!

Having more does not improve the wire mess, (much).



Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[MacRae]

mmdgatech,
Your concern is well founded. Per the letter of the NEC these are considered temporary power taps. Thus, they are not allowed for a permanent intallation.

Ian Rines
Harris Corporation
Palm Bay,FL

 

[stevenal]

And how exactly would one install a power strip permanently? By the very nature of its plug in connections, it is not permanent. With out altering the device, I don't see how a power strip can be installed permanently. Just meet the prohibitions of 400.8.

 

[electricpete]

When I look under my desk here at work I see something that looks like a permanent power strip. It is metal strip built in along the bottom of the cubicle wall with double outlets every two feet or so. There is no way in the cubicles to unplug the strip so it appears permanent.

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[electricpete]

btw Keith I am jealous of your collection of electronics, especially that lava lamp. We just moved a different home and my study has merged into the master bedroom, so tidiness of the computer area is a subject of intense current interest in my household.

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[stevenal]

Pete,

Same in my office. The cubicle walls are not part of the building, though, and are moved quite frequently. A flexible cord and plug attach the system to building wiring. Probably a listing somewhere on these things too. If your walls are permanent, and the strips are wired into rather than plugged into the building wiring, then the receptacles are permanent and also okay provided they otherwise meet code.

 

[JDPE]

I work for UL so here is the deal with power strips, formally called relocatable power taps:

USE AND INSTALLATION
This category covers relocatable power taps rated 250 V ac or less, 20 A or less. They are intended for indoor use as relocatable multiple outlet extensions of a single branch circuit to supply laboratory equipment, home workshops, home movie lighting controls, musical instrumentation, and to provide outlet receptacles for computers, audio and video equipment, and other equipment. They consist of one attachment plug and a single length of flexible cord terminated in a single enclosure in which one or more receptacles are mounted. They may, in addition, be provided with fuses or other supplementary overcurrent protection, switches, suppression components and/or indicator lights in any combination, or connections for cable, communications, telephone and/or antenna.

Relocatable power taps are intended to be directly connected to a permanently installed branch circuit receptacle. Relocatable power taps are not intended to be series connected (daisy chained) to other relocatable power taps or to extension cords.

Relocatable power taps are not intended for use at construction sites and similar locations.

Relocatable power taps are not intended to be permanently secured to building structures, tables, work benches or similar structures, nor are they intended to be used as a substitute for fixed wiring. The cords of relocatable power taps are not intended to be routed through walls, windows, ceilings, floors or similar openings.

Hope this helps

 

[itsmoked]

Yeah JDPE it does! Thanks.

The only thing I find strange is if they aren't supposed to be permanent, why do they all have ways to screw them down?

Also I guess I should plug them all into the UPS not each other (daisy chain).

electricpete; The wiring mess that all creates is .. astounding. Your better half would probably get hypoxic just looking at it.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[DonPhillips]

I worked a project in 1996 or so where the electrical inspector was not going to accept power strips from each poke-through device serving 3 workstations during an electrical final inspection. He wanted a poke-through for each workstation, citing the temporary power tap section of NEC. We had designed this 300,000 sf, 5 story building with 1800 workstations around 1 poke-through for 3 workstations, each poke-through on a 20A circuit.

We had argued the power-strips we were planning where UL listed as a TVSS device, met at the job site, he confirmed our power-strip was correctly listed and being used per hte listing as a TVSS device, and then agreed to accept them. Saved us about $100,000 and kept us on schedule.

Don Phillips