Motors & Equipment第 102 / 120 题
A photovoltaic source circuit uses modules with a rated short-circuit current of 10 amperes. What minimum conductor ampacity is required before any temperature or conduit-fill adjustments?
a.12.5 amperes
b.15.6 amperes
c.10 amperes
d.20 amperes
解析
The maximum circuit current is 125 percent of the rated short-circuit current, or 10 x 1.25 = 12.5 A, and the conductor must then be sized at 125 percent of that value without adjustment factors: 12.5 x 1.25 = 15.6 A. The 12.5-ampere answer stops after only the first multiplier, and 10 amperes ignores both.
法律依据: 2023 NEC §690.8免费刷完整 120 道题库 — 无需注册。
同考点相关题目
- A surface-mounted luminaire with a completely enclosed light source is installed in a clothes closet. What is the minimum clearance to the nearest point of the defined storage space?
- A recessed luminaire that is NOT identified for insulation contact must maintain what minimum clearance from thermal insulation?
- A generator nameplate current rating is 200 amperes. What minimum conductor ampacity is required from the generator terminals to the first overcurrent device?
- A motor with a service factor of 1.16 will not start because the overload device trips, even though it is sized at 125 percent of nameplate current. To what maximum percentage may the overload device be increased?
- What is the maximum non-time-delay fuse permitted for branch-circuit short-circuit and ground-fault protection of a 34-ampere three-phase squirrel-cage motor, using the next standard size allowance?
- A 20-horsepower, 208-volt three-phase motor has a table full-load current of 59.4 amperes. What is the minimum copper branch-circuit conductor at 75 degrees C terminations?