1/2” EMT to 3/8” FMC

[rojay]

Can anyone find a code section that would prohibit the use of a listed fitting to change over from 1/2”EMT to 3/8”FMC?

The application that I have in mind is a typical residential hard-wired dishwasher connection that complies with 348.20a guidelines (less than 6ft and supplying utilization equipment).
I understand that a Bridgeport 280-DC fitting that is intended for use to transition from EMT to NM cable is an obvious code violation but multiple manufacturers (including Bridgeport) make listed fittings for the application.

I’ve been told many times that there is a code issue with the transition from 1/2” EMT to 3/8” FMC but have never found anything in the code that supports that claim. A problem with the reduction in raceway size perhaps?

Any thoughts?

 

[petersonra]

Can anyone find a code section that would prohibit the use of a listed fitting to change over from 1/2”EMT to 3/8”FMC?

The application that I have in mind is a typical residential hard-wired dishwasher connection that complies with 348.20a guidelines (less than 6ft and supplying utilization equipment).
I understand that a Bridgeport 280-DC fitting that is intended for use to transition from EMT to NM cable is an obvious code violation but multiple manufacturers (including Bridgeport) make listed fittings for the application.

I’ve been told many times that there is a code issue with the transition from 1/2” EMT to 3/8” FMC but have never found anything in the code that supports that claim. A problem with the reduction in raceway size perhaps?

Any thoughts?

How about this one? 286-DC.

https://www.bptfittings.com/store/emt-to-fmc-transition-coupling-2073.html

 

[rojay]

How about this one? 286-DC.

https://www.bptfittings.com/store/emt-to-fmc-transition-coupling-2073.html

Yes, actually the 280-DCX is exactly the fitting I’m talking about! So the fact that there are listed fittings available to transition from 1/2” EMT to 3/8” FMC proves that there is no code violation in reducing the size of the raceway? I have been told by more than one inspector that there is some issue in reducing the raceway size- but I’ve never been able to find anything to back that up in the NEC. I’m getting the feeling it may be another BIS-SO code- (Because I Said So):happysad:

 

[Coppersmith]

I've never heard of a code violation for reducing raceway size. As long as the smaller raceway is still large enough for the wire/cables I dont see a problem. Reducers for various raceway types are available. I personally have used PVC and rigid reducers.

 

[LarryFine]

If an inspector failed me on such an installation, I would ask what is the proper application for the fitting.

Other options would be to use MC with the conductors already in it, or a handy-box with a blank cover.

 

[infinity]

I’ve been told many times that there is a code issue with the transition from 1/2” EMT to 3/8” FMC but have never found anything in the code that supports that claim. A problem with the reduction in raceway size perhaps?

Any thoughts?

There is no code issue. As stated they even make the proper listed fitting.

 

[kwired]

Yes, actually the 280-DCX is exactly the fitting I’m talking about! So the fact that there are listed fittings available to transition from 1/2” EMT to 3/8” FMC proves that there is no code violation in reducing the size of the raceway? I have been told by more than one inspector that there is some issue in reducing the raceway size- but I’ve never been able to find anything to back that up in the NEC. I’m getting the feeling it may be another BIS-SO code- (Because I Said So):happysad:

BIS-SO isn't good enough, they need to cite what code section is in violation. If they can't find one maybe nothing is being violated.