MC CABLE & FINAL CONNECTIONS

[Alwayslearningelec]

If a spec reads that MC is only able to be used to make final connections to light fixtures is that considered the "whip/fixture tail" to the j-box and not all the branch circuiting for the lighting? Don't know if that can be interpreted in different ways? i would say that is just the tails/whips? Thanks.

 

[stevebea]

If a spec reads that MC is only able to be used to make final connections to light fixtures is that considered the "whip/fixture tail" to the j-box and not all the branch circuiting for the lighting? Don't know if that can be interpreted in different ways? i would say that is just the tails/whips? Thanks.

Yes, thats how I interpret that. A whip to a junction box set on wall, bar joist, etc in close proximity.

 

[infinity]

If a spec reads that MC is only able to be used to make final connections to light fixtures is that considered the "whip/fixture tail" to the j-box and not all the branch circuiting for the lighting? Don't know if that can be interpreted in different ways? i would say that is just the tails/whips? Thanks.

I agree, we see this often when the building spec is for EMT only and no AC or MC cable.

 

[cdslotz]

Yep. That's a conduit only spec.
MC only allowed as final "whip" to fixtures.
It probably says somewhere, no longer than 6'

 

[stevenj76]

Sounds like a federal building.

It doesn't mean that it can only be six feet. That would only apply if it was a fixture whip with #18's.

I would run MC from jboxes, it wouldn't matter if it was thirty feet, as long as it was dedicated.

 

[infinity]

Sounds like a federal building.

It doesn't mean that it can only be six feet. That would only apply if it was a fixture whip with #18's.

I would run MC from jboxes, it wouldn't matter if it was thirty feet, as long as it was dedicated.

You're right, unless the spec defined the whip length as 6' or less you might get away with more when using MC cable. If the whips are 3/8" FMC then you're limited to 6' regardless of the conductor size within the whip.

 

[Alwayslearningelec]

And I was actually told the whips can't be MC because most of the time it's says fixture tails/whips are to be type SFF(??) wire insulation and MC does not come with that insulation. Is that correct? Thanks

 

[infinity]

I've never seen a spec for SFF type fixture wires. Those are a silicone rubber based insulation with a 150 degree C temperature rating. Sounds $$$$.