The short length of unlisted flexible metal conduit that serves this garage door opener was installed without an equipment-grounding conductor.
Per 250.118 of the 2002 NEC, “The equipment grounding conductor run with or enclosing the circuit conductors shall be one or more or a combination of the following:
“(6) Listed flexible metal conduit that is not listed for grounding, meeting all the following conditions:
“a. The conduit is terminated in fittings listed for grounding.
“b. The circuit conductors contained in the conduit are protected by overcurrent devices rated at 20A or less.
“c. The combined length of flexible metal conduit and flexible metallic tubing and liquidtight flexible metal conduit in the same ground return path does not exceed 1.8 meters (6 feet).
“d. The conduit is not installed for flexibility.”
About the Author
Joe Tedesco
Tedesco served the industry in many roles during his career. He was a director, senior electrical code instructor for National Technology Transfer, Inc. and American Trainco, Inc.. He was also a codes, standards and seminar specialist for the International Association of Electrical Inspectors and an electrical field service specialist for the National Fire Protection Association in Quincy, Mass. He ran his own business as an NEC consultant and is a Massachusetts licensed master electrician and journeyman electrician and certified electrical inspector (one and two family 2A; General 2B, and Plan Review, 2C). Tedesco also wrote articles for CEE News and EC&M (Code Violations Illustrated and What's Wrong Here?) for more than 15 years and helped launched the Moving Violations video series.
