I would like to install a portable outlet box near a work area in an unfinished basement. I have seen these installed in commercial buildings and educational laboratory type areas, always dropped from the ceiling with unarmored cable, hard-wired into a junction box. Would this be permitted in my specific case?

A few examples of the portable boxes:



  • I'm pretty sure the cable is made to take some weight and I would add hooks to strain-relieve the plugs you will be plugging in – ratchet freak Nov 17 '14 at 13:31
  • There will have to be GFCI protection (need not be AT this outlet, but this outlet needs to be covered BY it, since it's in a basement.) – Ecnerwal Nov 17 '14 at 17:08

You will need to have to provide proper strain relief of the flexible cord that drops down:

(from the NEC)

*368.56(B) Cord and Cable Assemblies. Suitable cord and cable assemblies approved for extra-hard usage or hard usage and listed bus drop cable shall be permitted as branches from busways for the connection of portable equipment or the connection of stationary equipment to facilitate their interchange in accordance with 400.7 and 400.8 and the following conditions:
(1) The cord or cable shall be attached to the building by an approved means.
(2) The length of the cord or cable from a busway plug-in device to a suitable tension take-up support device shall not exceed 1.8 m (6 ft).
(3) The cord and cable shall be installed as a vertical riser from the tension take-up support device to the equipment served.
(4) Strain relief cable grips shall be provided for the cord or cable at the busway plug-in device and equipment terminations.

Strain relief solutions are generally in the form of a metal finger-trap cages that tightens when the cable is pulled. for example:

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  • 1
    Would a grounded metal junction box with strain relief connections be permissible as the "busway plug-in device" in this context, or would busway need to be installed? – Alex Nov 17 '14 at 15:46

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