The UL for liquid tight flexible metal conduit says -
UL 360 (metal) -
"These requirements cover the 3/8, 1/2, 3/4, 1, 1-1/4, 1-1/2, 2, 2-1/2, 3, and 4 inch trade sizes of liquid-tight flexible steel conduit. The conduit covered is intended for installation in accordance with the National Electrical Code (NFPA 70) as raceway for wires and cables in motor circuits operating at potentials over 600 volts, in electric-sign circuits operating at potentials up through 1000 volts, over 1000 volts, and in other circuits operating at 0 – 600 V."
So...can a raceway system for a 15kv cable (non-motor circuit) use a flex conduit to accommodate movement or does that violate the flex-conduit's listing?
Is there another type of flex that is listed (NEMA, ANSI, UL, etc) for 15kv circuits?
What does one do when a 15kv circuit raceway needs to permit some flex?
Current question derived from Alaska installation where frost heave is major concern.
UL 360 (metal) -
"These requirements cover the 3/8, 1/2, 3/4, 1, 1-1/4, 1-1/2, 2, 2-1/2, 3, and 4 inch trade sizes of liquid-tight flexible steel conduit. The conduit covered is intended for installation in accordance with the National Electrical Code (NFPA 70) as raceway for wires and cables in motor circuits operating at potentials over 600 volts, in electric-sign circuits operating at potentials up through 1000 volts, over 1000 volts, and in other circuits operating at 0 – 600 V."
So...can a raceway system for a 15kv cable (non-motor circuit) use a flex conduit to accommodate movement or does that violate the flex-conduit's listing?
Is there another type of flex that is listed (NEMA, ANSI, UL, etc) for 15kv circuits?
What does one do when a 15kv circuit raceway needs to permit some flex?
Current question derived from Alaska installation where frost heave is major concern.
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