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Posted By: GWEnergy NEC- 314.23 (H) (1) - 08/05/22 05:31 PM
Does a SO cord drop need a threaded hub or can you use a blank cover or knock out from a 4 square or octagon box? Also is it allowed just to have a cord cap on end of SO cord or do you need a approved pendant box? I don't think using a 4 square box with k.o.'s is allowed for pendant boxes either.

Thanks for any help.
Posted By: gfretwell Re: NEC- 314.23 (H) (1) - 08/05/22 11:45 PM
The first question is answered in the title you posted.

(1) Flexible Cord. A box shall be supported from a multiconductor cord or cable in an approved manner that protects the
conductors against strain, such as a strain-relief connector
threaded into a box with a hub.

I suppose the second question is in the listing of the cord cap. (receptacle)
I know it is common to see pendants terminated with Russell Stoll or IEC 309 receptacles.
Posted By: Bill Addiss Re: NEC- 314.23 (H) (1) - 08/06/22 10:43 PM
So you could use a T-11 Box or similar?

How long has a threaded hub been required?
Posted By: gfretwell Re: NEC- 314.23 (H) (1) - 08/07/22 05:21 AM
Originally Posted by Bill Addiss
So you could use a T-11 Box or similar?

How long has a threaded hub been required?

The first place I see that language is a code change to the 1987 370.13(h).
Posted By: GWEnergy Re: NEC- 314.23 (H) (1) - 08/07/22 02:40 PM
Thanks for reply. As I understand it a T-11 is not allowed FD box would be...osha has a section on this.

I ended up using a rigid T with a dead leg on one side for support and a 4 square on the other to make connections.

You see a lot of cord drops with 4 square boxes or cord cap on the end of so cord but these are actually a code violation.
Posted By: gfretwell Re: NEC- 314.23 (H) (1) - 08/07/22 05:04 PM
I suppose using a T-11 (Bell box) would be a local call since it is a threaded entry but that probably actually gets back to the listing and a 110.3(b). I bet they say that box needs to be attached to something.
Posted By: gfretwell Re: NEC- 314.23 (H) (1) - 08/07/22 05:07 PM
I believe there are cord grips for some of the pin and sleeve receptacles that are listed for pendant use but that is not the same as a garden variety 5-15 receptacle cap you see on a field assembled/repaired extension cord.
Posted By: renosteinke Re: NEC- 314.23 (H) (1) - 08/07/22 11:13 PM
I seem to recall the “threaded hub pendant” first appearing around 2005. I still haven’t dug out my code library smile

The change came about after a prominent inspector made it a priority — even a holy cause — after his successful campaign to ban drywall screws. In the course of traveling to conduct seminars, he found many DIY extension cords with four-square boxes that had suffered from abuse. Hence the code change.

At that time I posted a picture here of a simple cord cap hanging from a pendant. I believe the conversation here was lively but inconclusive — with objections centering on whether the court cap was suitable for outdoor locations.

As far as strain relief is concerned, even UL is stumped. They have two wildly different standards and even they’re not sure when to apply each. Even 2-screw NM/FMC connectors are listed (look at the box) for gripping flexible cords in some applications. Other situations seem to require both Chinese handcuffs and compression clamps.
Posted By: gfretwell Re: NEC- 314.23 (H) (1) - 08/08/22 01:41 AM
Threaded hub for flexible cords was in the 1987 in article 370. In 2002 that got moved to a new article 314.23(h) and they added "pendant" to the language.
Posted By: renosteinke Re: NEC- 314.23 (H) (1) - 08/09/22 11:34 AM
Thank you. Well, my mind hasn’t completely lost I 😁
Posted By: NORCAL Re: NEC- 314.23 (H) (1) - 08/10/22 04:11 AM
Originally Posted by renosteinke
Thank you. Well, my mind hasn’t completely lost I 😁

Where have you been all this time? You dropped off the face of the earth. grin
Posted By: renosteinke Re: NEC- 314.23 (H) (1) - 08/10/22 03:13 PM
Well, I did move to Arkansas …. 😁

I worked a bit for a pipe mill. Hired for electrical work, never had any connection to the trade until the last few months.

I posted some pics here of some wildly illegal installs there. They were most annoyed when the pics were brought to managements attention. My only duty at the end was adding timers to those heaters — which gave me the opening to make the installs code compliant. Task done, my services were no longer desired.

At that point I was ready to retire. Did a minor bit of inspection work for an operation that was a joke. Decided to focus on my house remodel and family issues. Suffice it to say I’ve been to plenty of funerals.

Last December 10 (2021) I looked at the radar — and immediately called a friend in the countryside with a warning. Ten minutes later her house was completely flattened by a Cat 4 tornado. She had another house 20 miles away that she occasionally rented out. Nice to have a spare!

Alas, scrappers got n and removed the wires and plumbing. So I’m back to work.
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