For flexible metal conduit, if flexibility is necessary after installation, unsecured lengths from the last point the raceway is securely fastened must not exceed _____ .
a) 3 ft for trade sizes 1/2 through 1 1/4
b) 4 ft for trade sizes 1 1/2 through 2
c) 5 ft for trade sizes 2 1/2 and larger
d) all of the above
See answer and applicable Code reference
The correct answer is: d) all of the above
The rules for securing and supporting Type FMC can be found in Sec. 348.30 of the 2011 NEC. The maximum unsecured distances based on the trade sizes shown above are noted in 348.30(A), Exception No. 2.
