Q. Where a transient voltage surge suppressor (TVSS) is installed, the TVSS shall comply with which of the following?
- The rating of the TVSS shall be equal to or greater than the maximum continuous phase-to-ground power frequency voltage available at the point of application.
- TVSS shall be a listed device.
- TVSS shall be marked with short circuit current rating and shall not be installed at a point on the system where the available fault current is in excess of that rating.
- TVSS shall not be installed on ungrounded systems, impedance grounded systems, or corner grounded delta systems unless listed specifically for use on these systems.
- All of the above.
All are these are requirements of a TVSS installation. See Sections 285.1, 285.3, 285.5, and 285.6 of the NEC.
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