Flex conduit for "long" 120 runs?

[jragain]

I have two 120V circuits in my garage that are currently surface mounted in EMT. I want to change their routes. Each new run would be about 40-50 feet long. I have access to a couple hundred feet of free flex conduit, but I want to keep things safe and legal. Am I OK to use flex for the entire run(s), or do I need to buy the EMT and get out the bender? Thanks.

 

[Charles (in GA)]

What kind of "flex conduit" are you talking about?

Charles

 

[jragain]

flexible metal

 

[Delta74]

If this is the Flex i am thinking about, better check your codes, usually you are restricted to no more then 6 feet, if its BX ( ac-90 ) has the wires in it, you could run thousands of feet no problem, just use the anti-shorts, and proper connectors, and no problems.

 

[Gooch]

there is no NEC requirement that i can remember on length of FMC.


i will say this though, if you plan to install the FMC then pull wire, it will be a major PITA.

 

[jragain]

I forgot about the difficulty of pulling the wire thru the fmc. Thanks.

 

[Norcal]

If flex/greenfield is used, plan on running a grounding conductor too....

 

[wanna_be]

I believe the 6' is only when it is unsecured. Like a drop going to light fixture or something like that.

 

[ddawg16]

I bet you could sell the flex and make enough money to buy the EMT and some of the wire.....

Someone did a bunch of wiring in my in-laws garage using flex....looks like **** and is hanging down.....something else to fix for them when I get time.

 

[Adrien]

If this is the Flex i am thinking about, better check your codes, usually you are restricted to no more then 6 feet, if its BX ( ac-90 ) has the wires in it, you could run thousands of feet no problem, just use the anti-shorts, and proper connectors, and no problems.

Incorrect. There's no limit on the length of Flexible Metal Conduit.

there is no NEC requirement that i can remember on length of FMC.

i will say this though, if you plan to install the FMC then pull wire, it will be a major PITA.

Correct.

If flex/greenfield is used, plan on running a grounding conductor too....

An Equipment Grounding Conductor is only required if it's to remain flexible and not securely fastened. If it's not to remain flexible the FMC can be used as the Equipment Grounding Conductor.

I believe the 6' is only when it is unsecured. Like a drop going to light fixture or something like that.

Correct.

I bet you could sell the flex and make enough money to buy the EMT and some of the wire.....

Someone did a bunch of wiring in my in-laws garage using flex....looks like **** and is hanging down.....something else to fix for them when I get time.

Also correct.

Also, if you do decide to run the FMC it needs to be secured 12" from each termination and also every 4.5'.

Adrien

 

[dwilliams35]

My code book's at work, but as I remember the main thing about the 6' is the grounding: if you've got a separate grounding conductor in the conduit, all you have to worry about is securing it. I'd go back with EMT myself. Just looks better, and EMT is pretty cheap.

 

[Norcal]

Incorrect. There's no limit on the length of Flexible Metal Conduit.



Correct.



An Equipment Grounding Conductor is only required if it's to remain flexible and not securely fastened. If it's not to remain flexible the FMC can be used as the Equipment Grounding Conductor.



Correct.



Also correct.

Also, if you do decide to run the FMC it needs to be secured 12" from each termination and also every 4.5'.

Adrien

If in excess of 6 feet a ECG must be used the greenfield is no longer suitable for a grounding path.

 

[klhitman]

we were running some through some hvac units at work and some engineers came in and said the the runs could only be 4ft long by code. me and the guy i work with tried to argue that we never seen that in the code book. but we had to fix it or they wouldn't buy the unit. so to this day we run everything in EMT unless its 4ft or less.