Can anyone explain this Code Article on Flexible Cords/Cables

[busman]

All,

We all know that 400.7 (reprinted below from 2014 NEC in case you don't have the book with you) gives us the permitted uses of Flexible Cords and Cables. What I don't get is the part in 400.8 that says, "Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following:" and lists 4 conditions (also below). It appears that nothing in 400.7 would override 400.8, so why say, " Unless specifically permitted in 400.7". Why not just say those uses are prohibited.

As an example, what condition in 400.7 would allow a cord thru a wall or ceiling?


I know this forum has some real word jockeys, so your opinions appreciated.

Thanks,

Mark

400.7 Us es Permitted
(A) Uses . Flexible cords and cables shall be used only for the
following:
(1) Pendants.
(2) Wiring of luminaires.
(3) Connection of portable luminaires, portable and mobile
signs, or appliances.
(4) Elevator cables.
(5) Wiring of cranes and hoists.
(6) Connection of utilization equipment to facilitate frequent
interchange.
(7) Prevention of the transmission of noise or vibration.
(8) Appliances where the fastening means and mechanical
connections are specifically designed to permit ready
removal for maintenance and repair, and the appliance is
intended or identified for flexible cord connection.
(9) Connection of moving parts.
(10) Where specifically permitted elsewhere in this Code.
(11) Between an existing receptacle outlet and an inlet, where
the inlet provides power to an additional single receptacle
outlet. The wiring interconnecting the inlet to the single
receptacle outlet shall be a Chapter 3 wiring method. The
inlet, receptacle outlet, and Chapter 3 wiring method,
including the flexible cord and fittings, shall be a listed
assembly specific for this application.
(B) Attachment Plug s. Where used as permitted in 400.7(A)(3),
(A)(6), and (A)(8), each flexible cord shall be equipped with an
attachment plug and shall be energized from a receptacle outlet
or cord connector body.
Exception: As permitted in 368.56.
400.8 Uses Not Permi tted
Unless specifically permitted in 400.7, flexible cords and cables
shall not be used for the following:
(1) As a substitute for the fixed wiring of a structure
(2) Where run through holes in walls, structural ceilings, suspended
ceilings, dropped ceilings, or floors
(3) Where run through doorways, windows, or similar openings
(4) Where attached to building surfaces

 

[luckylerado]

As an example, what condition in 400.7 would allow a cord thru a wall or ceiling?

Signs
Sump pump alarm box in an elevator pit
Projector mounted in a ceiling
Automatic Window blinds
Some CCTV Cameras

 

[busman]

Signs
Sump pump alarm box in an elevator pit
Projector mounted in a ceiling
Automatic Window blinds
Some CCTV Cameras

Thanks for the answer, but I think that is a list of typical uses where cords penetrate structure, but I can't see anything in 400.7 that makes that permissible in those cases.

Mark

 

[mwm1752]

Unless specifically permmitted refers to any use in 400.7 that conflicts with not allowed in 400.8 -- so you've answered you own question.

 

[GoldDigger]

As a practical matter, the only use in 400.7 that was specifically designed to be used inside a closed wall space and does not make sense outside a wall is that which is described in (11). It is not obvious from the description, but the ROP and context relate this specific description to systems designed to be fished through a wall to provide a receptacle outlet behind the mounting location of a wall mount TV. That flexible cord is fed from an existing receptacle outlet or j-box which is already part of the building wiring system.

 

[ActionDave]

Thanks for the answer, but I think that is a list of typical uses where cords penetrate structure, but I can't see anything in 400.7 that makes that permissible in those cases.Mark

Here is a link to see where this whole thing with 400.7 got started.......http://forums.mikeholt.com/showthread.php?t=134709&highlight=powerbridgeHere is another one about the code change.........http://forums.mikeholt.com/showthread.php?t=135017&highlight=powerbridge

 

[iwire]

As an example, what condition in 400.7 would allow a cord thru a wall or ceiling?

None, the example you chose has no place it is allowed.