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Elevated cable trays - when could these be considered subject to physical damage and unsupported tray cable not allowed per the NEC?

bdn2004

Electrical
Jan 27, 2007
795
A guy at an established site (not new construction) got up in a mechanical lift doing some retrofit work, that goes on continuously at this site.
Many of the tray cables coming out of the elevated cable trays have only strain relief at the tray then onto their conduit that extends up from the equipment located on the floor. When up in the lift, for whatever reason the lift hit that section of an unsupported cable and it caused a fault. Is this typical installation an NEC violation because of the continuous maintenance and retrofit work that goes on ? On an every day basis seems the NEC exception would apply.

NEC 336.10 Exception to 7... which states:

Where not subject to physical damage, Type TC-ER shall be permitted to transition between cable trays and between cable trays and equipment or devices for distance not to exceed 1.8m (6 ft) without continuous support. The cable shall be mechanically supported where exiting the cable tray to ensure that the minimum bending radius is not exceeded.
 
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