When installing polyvinyl chloride conduit (PVC) or reinforced thermosetting resin conduit (RTRC) as a Class I, Division 1 wiring method for an underground installation in a tank farm area, which statement is not true?
A. The conduit(s) must be installed with 24 in. of cover over the top of the concrete, which encases the conduit.
B. The conduit(s) must be covered by at least 2 in. of concrete.
C. The conduit(s) must be encased in a concrete envelope by at least 2 in. of concrete.
When installing a transformer (such as a 75kVA unit), the disconnecting means for this piece of equipment shall be _________, and the location of the disconnecting means shall be ______ marked on the transformer.
Q. Exposed non-current-carrying metal parts of small wind electric systems, such as towers, turbine nacelles, other equipment, and conductor enclosures shall be connected to an equipment grounding conductor [in accordance with 250.134 or 250.136(A)] at what voltage level?
A. All voltage levels
B. 50V or more
C. 600V or more
D. 1,000V or more
Fill in the blanks with the appropriate answers.
Q. Where a building exceeds _______ stories, or ____ ft or more in height, overhead lines shall be arranged, where practicable to, so that a clear space (or zone) at least 6 ft wide will be left either adjacent to the buildings, or beginning not over 8 ft from them to facilitate the raising of ladders when necessary for fire fighting. Note: This relates to conductors operating at 600V or less nominal.
Where in the NEC does it state, "completed wiring installations shall be free from short circuits, ground faults, or any connections to ground other than as required or permitted elsewhere in the Code?”
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