Use of Rubber Cord in Industrial Establishment

[Jljohnson]

The recetacles and cord caps are twist-lock. This was designed since the receptacles are installed face down in the ceiling. It wouldn't take much cord weight to pull loose from a straight blade receptacle.

 

[jhuratiak]

This 400.7/400.8 is one of the hardest articles to get a handle on. I'll post my 2 cents and see what happens. In the 1999 code process Article 400.8, Exception was changed. Based on the IAEI Anaylsis of Change for 1999 the only time you can attach to the building is if you are coming from a busway (Article 364-8(b) 1999) Article 368-56. So what they did was eliminate the ability to come out of a junction box or wireway and attach to the building. Article 400.7 (B) requires an attachment plug and the cord must be energized from a receptacle. How do you address the issue of strain relief and spring tensioning if you can't attach to the building? My interpretation is that the only time you can run cord and attach to the building is from a busplug.

 

[petersonra]

I don't see where what he describes constitutes any of the above. I don't think it's building wiring. I think the building wiring stops at the twistlocks.

I agree. This is not part of the premises wiring, anymore than a lamp is.

 

[jtinge]

Mike Holt's figure 400-2 in his Article 400.7 Flexible Cords (don't have the link) shows the use of flex cord pendants from a box in the ceiling. This is acceptable for connecting utilization equipment to facilitate frequent interchange. What you describe, if I understand correctly, is connection of a workbench with outlets installed with permanent wiring methods (boxes and conduit) which then transistions to a rubber cord and plug and it then connected to the drop pendant cord. If you consider the workbench as utilization equipment, this cord connection to the drop pendant is ok. I don't think the workbench supplied by a rubber cord, however, meets the definition of utilization equipment since the outlets are distributing power on the workbench and not utilizing the power. I think the intent of the "uses permitted" section of 400.7(A)(6) was geared toward equipment like drill presses, lathes, or other large equipment that have a cord connection.