MC cable connectors required?

[Stevenfyeager]

My customer has fastened my stubbed out mc cables tightly as he installed sheet metal siding inside of warehouse. He wants me to surface mount outlet boxes. I'm fine with that except he securely fastened them, I had left a little play so I could install mc connectors on two cables and push them back a little so my box would fasten tight onto the wall. I'm glad he installed solid wood in each location, as I have a solid way to fasten my outlet box. But my question: is an mc cable connector required where the mc cable enters the back of a metal box ? Thank you.

 

[LarryFine]

Yes. I have used these successfully when the MC sheath ended at the wall:

 

[HEYDOG]

Yes. I have used these successfully when the MC sheath ended at the wall:

Are those listed for M.C.?

 

[LarryFine]

Are those listed for M.C.?

I don't know if they're listed for MC, but they certainly do fit it. I just used some on 12-3.

 

[infinity]

Are those listed for M.C.?

I thought that they're only listed for FMC. Internal fittings are mentioned in Table 348.22.

 

[HEYDOG]

I thought that they're only listed for FMC. Internal fittings are mentioned in Table 348.22.

I totally agree!

 

[Stevenfyeager]

I just read 314.17. Cables must be secured to box. I wish I had talked with the steel installers about my plan.

 

[hbiss]

My customer has fastened my stubbed out mc cables tightly as he installed sheet metal siding inside of warehouse.

Looks like it's on your customer to pay to make the necessary changes. What business did he have to do that??

How did he fasten them? Can you use a 3-1/2" hole saw to make a hole in the sheet metal behind where the box is going to go and then you could reach in and release the cables? Box would cover the hole.

-Hal

 

[winnie]

There are the MC connectors designed to work from _inside_ the box.

The cable goes through the ko, then you put the connector on and snap the connector to the ko.

I've used these when I've fished MC in old work situations. Not sure how much give you need on the cable for your situation.

Example: https://www.bptfittings.com/store/3...-cable-connector-insulated-zinc-die-cast.html

 

[acrwc10]

There are the MC connectors designed to work from _inside_ the box.

The cable goes through the ko, then you put the connector on and snap the connector to the ko.

I've used these when I've fished MC in old work situations. Not sure how much give you need on the cable for your situation.

Example: https://www.bptfittings.com/store/3...-cable-connector-insulated-zinc-die-cast.html

those are nice, I have yet to see them installed, but I guess that's the point.

 

[Stevenfyeager]

Thank you very much. My worker so far was able to oscillate tool through the steel and enlarge the hole, and found some loose play, and used 'two into one' mc connectors. Still more time than I had planned for.