Questions With Correct Answers
Which Article of the NEC covers grounding?
article 250
Which of the following is a 90 degree, explosion proof fitting?
GUAL
What is a dropout plate?
Metal plate with a curved surface for cable to follow as it passes from the tray
All of the following are common service voltages in the United States EXCEPT:
372/575 3-PHASE, 4-WIRE
What does a GFCI breaker do?
Opens a circuit to prevent operation of an electrical device
,What will happen when one or more coils in a winding are grounded?
The motor will automatically blow fuses
Eight incandescent lighting fixtures are to be installed. Each fixture is 120- volts, with a
200-watt lamp. What is the total connected load?
13.3 amps
The must be grounded in a bussed gutter if used as the main service equipment.
Neutral busbar
When wall mounting cable tray, ensure that
The building structure is strong enough to support the tray system
The purpose of sealing cable ends when reels of cable are in storage is
To keep moisture from creeping in
The outer covering on liguid-tight flexible metal conduit is used for
,A moisture seal
A good electrical connection should
Be mechanically and electrically secure
The symbol normally used for duplex
Circle with two parallel lines drawb through it
Disconnecting means are covered in
NEC Section 110-22
In relation to switches, the term throw refers to the
Number of internal operations that a switch can perform
A 3-phase, 4-wire, 480v service requires ______ current transformer(s)
3
Services conductors and equipment are covered in
, NEC Article 230
The NEC required that all receptacles installed on 25 amp and 20 amp branch circuits
be ______ receptacles
Grounding
A transformer with the primary of 400 turns and a secondary of 300 turns has a _____
Step-down turns ratio of 4:3
The circular mil is based on the
Cross-sectional area of the wire
Of the termination classes listed below, ____ is the only one that provides a seal
against external elements.
Class 1
Unless otherwise noted. the calculations in AC circuits _____ values.
Rms