Liquidtight flexible metal conduit (LFMC)

[Dsg319]

I’ve heard “tales” of lfmc only being allowed in lengths of 6ft, however I ready through article 350, and couldn’t find anything about a maximum length. Only supporting measurements and such.

I did however see where it was only allowed 6ft for service conductors in 230.43.

BUT, is there anything that mentions a maximum length in a regular scenario such as a raceway for branch circuits?

 

[infinity]

No general limit in the NEC. Some places do have local amendments to no more than 6'.

 

[Greentagger]

Elevators, 620.21(A)(1)(2), used as a egc as a raceway per 250.118(6)

 

[James L]

In our area, it's common that we're allowed up to 6ft, but that's generally "past the last strap"

This pertains to things like air conditioners, where the whip gets strapped by a disconnect and then free-airs to the unit.

Other instances might be electric water heaters, air handlers, etc where strapping isn't feasible

 

[SSDriver]

I think the 6' rule you are hearing comes from using the LFMC as an EGC. If you want to use it as the circuit EGC it is limited to 6'. If you pull an EGC of the wire type you are fine to go longer.

250.118 (6)
Types of Equipment Grounding Conductors

(6) Listed liquidtight flexible metal conduit meeting all the
following conditions:

a. The conduit is terminated in listed fittings.

b. For metric designators 12 through 16 (trade sizes 3⁄8
through 1⁄2), the circuit conductors contained in the
conduit are protected by overcurrent devices rated at
20 amperes or less.

c. For metric designators 21 through 35 (trade sizes 3⁄4
through 11⁄4), the circuit conductors contained in the
conduit are protected by overcurrent devices rated
not more than 60 amperes and there is no flexible
metal conduit, flexible metallic tubing, or liquidtight
flexible metal conduit in trade sizes metric designators 12 through 16 (trade sizes 3⁄8 through 1⁄2) in the
ground-fault current path.

d. The combined length of flexible metal conduit and
flexible metallic tubing and liquidtight flexible metal
conduit in the same ground-fault current path does not
exceed 1.8 m (6 ft).

e. If used to connect equipment where flexibility is
necessary to minimize the transmission of vibration from equipment or to provide flexibility for
equipment that requires movement after installation, an equipment grounding conductor shall be
installed

 

[infinity]

I think the 6' rule you are hearing comes from using the LFMC as an EGC. If you want to use it as the circuit EGC it is limited to 6'. If you pull an EGC of the wire type you are fine to go longer.

250.118 (6)
Types of Equipment Grounding Conductors

Yes pull in an EGC and there is no length limit.

 

[Dsg319]

Yes pull in an EGC and there is no length limit.

We do a lot of work with a gas company called Equitrans. Formally known as EQT. They spec out 18”max . Unless your a vendor pre-fabbing a skid than you sling it all over like rope.