Equipment' 2023 Questions and Answers
Which of the following is true with regard to switchboards
Switchboards are used to subdivide large blocks of power
When installing wiring within switchgear, use self adhesive cable ties every ___.
12" (300mm)
The maximum voltage that a piece of equipment can withstand is known as its
____.
Basic impulse insulation level (BIL)
Bolted pressure switches are often used in place of ___.
Circuit breakers
A transformer's temperature rise rating refers to ___.
The maximum elevation above ambient temperature that the transformer can withstand
without insulation damage
A service has a three-phase supply with 14 single-pole circuits and 4 three-pole
circuits. The minimum number of poles required is ___.
30
Per NEC Section 408.3(E)(1), AC phasing in switchboards must be labeled ___.
A,B,C from front to back, top to bottom, or left to right when read facing the front of the
switchboard
On a typical electrical diagram, the standard abbreviation for a phase meter is __.
PH
The typical insulation resistance of equipment rated at 480V is ___.
100 megohms
A typical overpotential test voltage for a used piece of equipment with a nominal
voltage class of 600V is ___.
2,000 VDC
A ground fault relay should be mounted in an enclosure ___.
In a vertical position with the terminal block at the lower end
In Industrial applications, medium voltage may refer to systems rated over ___.
1,000V up to 35,000V
The term Interrupting rating refers to the ___.
maximum current a device will safely interrupt at rated voltage
Which of the following is NOT a general classification of circuit breakers?
Fuse circuit breaker
A 4,000A switchboard requires a minimum distance from the phase bus to the
closest steel member of ____.
6" (150mm)
When an unintended path is established between an ungrounded conductor and
ground, it is called a(n)____.
ground fault
A transformer rated at more than 500kVA is considered a(n) ___.
power transformer
The term capacity on a transformer nameplate refers to ____.