Book #1 Flashcards
What type of wire, when ran in free air, can carry the most current?
Bare Copper
What secondary terminal should be grounded?
X0
The proper method of cutting the armored covering off armored cable is:
Diagonally across the weave with a hacksaw
Anti-short bushings are used for protecting conductors in
AC
A device for measuring the diameter of a motor shaft is:
Micrometer
What is used to prevent scaffolding from toppling due to high center of gravity
Outriggers
A point in the wiring system where current is taken to supply utilization equipment is called:
An outlet
A three phase supply may be obtained by using two transformers if:
An open delta connection is used
The functions of grease in the bearings of an electrical motor is to:
Reduce heat from mechanical friction
What is the proper termination procedure when installing free air rated single conductors for a feeder installation with a calculated load of 400 amps
Aluminum to Aluminum Plates
While working at a motor control center, a 208 volt magnetic starter for a 15 HP motor is humming louder than the adjacent starters. Which component requires repair?
Shading Coil
Service conduit connected to an underground supply system shall be sealed with a suitable compound to prevent:
the entrance of moisture
Three way switches may be connected only in
the ungrounded circuit conductor
What is another term for root means square
Effective Value
What type of single phase motor would best be suited to be used for a domestic refrigerator?
Capacitor start
An ohmmeter is connected across a discharged capacitor anf the needle stabalizes at approximately 100K ohms. The Cap is?
Leaky
shorted = Zero
Good= infinite
A 75 KVA outdoor, pole mounted transformer is usually cooled by means of:
Refined mineral oil
A shading coil in a magnetic switch is intended to:
reduce chattering
An atom that has lost or gained electrons:
is said to be ionized
What two quantities comprise the total power of an AC circuit?
True power and reactive power
A DC generator is a rotating machine that converts:
Mechanical energy to electrical energy
The centrifugal switch in a single phase motor serves the purpose of:
opening the start winding when the motor has almost reached running speed
A safety precaution to follow when using a potential transformer is to:
Ground the secondary
The drawings most often used in maintenance work are:
Schematics and wiring diagrams
The type of diagram that is consulted to find location and interconnection of parts is called a:
Wiring Diagram
