(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.
314.23.(H)(1):
I don't think it necessarily means the box must have a threaded hub, it is giving us an example of something acceptable more so than it is telling us we must do it a particular way.
What about boxes that are designed specifically for use as pendant boxes? Not all of those have "hubs" yet usually have some reinforcement in the area of the cord entry.
I don't follow-- a 4" sq. doesn't have a hub or threads so IMO, the ko's are not acceptable.Thanks but still doesn?t say anything about the KOs and that is what OSHA hung my customer on. And said it was NEC.
Thanks but still doesn?t say anything about the KOs and that is what OSHA hung my customer on. And said it was NEC.
And 314.23(H)(1) only suggests a threaded hub and does not have any wording that absolutely requires one.I don't follow-- a 4" sq. doesn't have a hub or threads so IMO, the ko's are not acceptable.
And when did OSHA start citing NEC? I thought they went by 70E with things they look at? Is there anything concerning this topic in 70E?
And 314.23(H)(1) only suggests a threaded hub and does not have any wording that absolutely requires one.
And when did OSHA start citing NEC? I thought they went by 70E with things they look at? Is there anything concerning this topic in 70E?
And 314.23(H)(1) only suggests a threaded hub and does not have any wording that absolutely requires one.
A box with threaded hubs has no KOs, neither will a listed pendent box with or without threaded hubs.
OSHA is exactly why I know about this as we have had to remove standard boxes after OSHA inspections and is now why I only use FS style boxes for cord drops now.
Is OSHA's concern the potential abuse removing additional KO's? A cord grip in one opening with no larger concentric/eccentrics is not going to be any different than an opening with same cord grip in a listed pendant box. That I can understand.
I kind of assumed they didn't like boxes with easy to remove KO's for that reason. I have seen many used for this type of application and often they will have KO's either partially pushed in or completely missing, sometimes even rattling inside the box. I don't care for them myself for this purpose because they often do that.I was once told, the issue is that some knockouts can be 'pushed in' simply with a thumb or finger during normal operation.
Our OSHA people tend to want the 'yellow plastic/rubber' boxes (i.e. from Hubbell or Woodhead) as they leave less of an impression than an FS box, when someone walks into one.
This doesn't make sense to me - what about standard surface mounting? The KOs are still right there for the pushing...I was once told, the issue is that some knockouts can be 'pushed in' simply with a thumb or finger during normal operation.
This doesn't make sense to me - what about standard surface mounting? The KOs are still right there for the pushing...
A few years ago we installed a load of Starline Track Busway and all the 120 volt drops were done with quad plates and 1900 boxes with out KOs and a strain relief connector that is were I saw the boxes and when the customer said that is what OSHA wanted and it was a NEC requirment it rang a bell. But still can't find it in the code book.