Flex connectors unsupported in switchgear

[Will B]

3" flex was run from the 800 amp, 480V switchgear through the 2nd floor to a Jbox in the ceiling below. In the switchgear, the core and KO in the floor of the switchgear are the same diameter, which is also too small for a 3" flex connector. As you can see in the picture, the electrical contractor installed the flex connector, but has it resting on the bottom of the switchgear, unsupported.

I couldn't find any code violation, but I do believe that a bonding bushing on the flex connector is required. Not sure why they didn't at least install EMT sleeves through the floor and then convert to flex instead. Can you guys comment on the install?

Thanks!


PS - Sorry if the picture is too large for some, it looks just right on my screen.

 

[augie47]

Don't see where it would be much different than doing so with conduit.
Since that size flex can't normally be used as a grounding conductor the need for a grounding bushing would depend on how it was terminated at the other end, IMO.
If I were inspecting, at first glance, I would be curious as to the need for fire caulk and what looks like an undersized equipment grounding conductor.

 

[Will B]

Thanks for replying, Augie47. All of the 3" flex runs to a pull can nearby in the ceiling of the 1st floor, then smaller conduits run to equipment. My thinking is that if EMT was used and the cores were larger, then the EMT connectors could be tightened to the metal base of the switchgear so if wouldn't be free to move around as it currently can.

 

[augie47]

grout

 

[infinity]

Is the bottom of that enclosure metal? It looks like more than 3" so it might not comply with this:

408.5 Clearance for Conductor Entering Bus Enclosures.
Where conduits or other raceways enter a switchboard,
floor-standing panelboard, or similar enclosure at the bot-
tom, sufficient space shall be provided to permit installation
of conductors in the enclosure. The wiring space shall not
be less than shown in Table 408.5 where the conduit or
raceways enter or leave the enclosure below the busbars,
their supports, or other obstructions. The conduit or race-
ways, including their end fittings, shall not rise more than
75 mm (3 in.) above the bottom of the enclosure

 

[Joe Villani]

Flex connectors unsupported in switchgear

Take a look at 300.10.

I would also look at 300.12. The installation in the picture does not meet exception 2.

 

[jusme123]

Take a look at 300.10.

I would also look at 300.12. The installation in the picture does not meet exception 2.

can you explain why it does not meet the exception #2?

 

[Will B]

Thank you all. I'll take a look at the articles listed above in the morning.

 

[infinity]

can you explain why it does not meet the exception #2?

He might be thinking that the bottom of the enclosure is metal and the connectors are not attached to it. After looking again it appears that there is a metal plate covering the holes in the floor so 300.12 wouldn't apply but Ex(2) would.

 

[Will B]

infinity, you are correct. I just confirmed that the contractor did lay a metal sheet on the floor. I'm unsure why this was done, however.