Ecmweb 20437 2017 Nec Changes Promo Image 0
Ecmweb 20437 2017 Nec Changes Promo Image 0
Ecmweb 20437 2017 Nec Changes Promo Image 0
Ecmweb 20437 2017 Nec Changes Promo Image 0
Ecmweb 20437 2017 Nec Changes Promo Image 0

Code Quiz: Disconnecting Means for Multiwire Branch Circuits

Nov. 20, 2018
Refresh your knowledge of the Code requirements for multiwire branch circuits.

The disconnecting means for multiwire branch circuits of low-voltage suspended ceiling power distribution systems shall simultaneously disconnect all _______conductors, including the _________ conductors.

A) supply / grounded
B) identified / equipment grounding
C) phase / grounding
D) none of the above

See the answer below.

Answer: A

Article 393 of the 2017 NEC covers the installation of low-voltage suspended ceiling power distribution systems. As specifically noted in Sec. 393.21(B), “The disconnecting means for multiwire branch circuits of a low-voltage suspended ceiling power distribution systems, shall simultaneously disconnect all supply conductors, including the grounded conductors.”

Owen is the owner and president of National Code Seminars and the holder of master electrician certifications in 46 states. He can be reached at [email protected].

About the Author

Steven Owen

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