Equipment & SystemsQuestion 335 of 521
When is a primary protector required on a communications circuit?
a.Never required
b.Where the circuit is exposed to lightning or to accidental contact with power conductors over 300 V to ground
c.Required only for indoor circuits
d.Required only for fiber-optic cable
Explanation
Section 805.90 requires a listed primary protector where communications circuits are exposed to accidental contact with power conductors over 300 volts to ground or are subject to lightning exposure. Fiber-optic cables carry no metallic conductors, so they do not require this electrical protector.
Law Reference: 2023 NEC §805.90Practice all 521 questions free — no signup required.
Related questions on this topic
- How must fire alarm circuit cables be installed and supported?
- What best characterizes a Class 2 circuit?
- How must Class 2 conductors generally be separated from electric light and power conductors?
- What is the minimum size of the bonding/grounding conductor for a communications system?
- The equipotential bonding for perimeter surfaces around a permanently installed pool must extend how far from the inside walls of the pool?
- A disconnecting means for pool utilization equipment such as a pump motor must be within sight and located at least how far from the inside walls of the pool?
Last reviewed: · editorial process
PrepPass Editorial Team · Verified against California CSLB C-10 Electrical Trade Examination · How we review