What short-circuited winding consists of a single turn of copper wire and acts on only a portion of the stator windings?
Shaded-pole (shading coil)
200
What part of a DC motor is the equivalent of an AC motor’s rotor (the rotating winding assembly)?
Armature
200
For a dual-voltage motor, the __________ connection is used for low voltage while the __________ connection is used for high voltage.
Parallel / series
200
A(n) __________ in a motor is caused by a load that exceeds the full-load rating of the motor.
Overload *
200
How is voltage unbalance measured in a 3-phase motor?
By comparing voltage readings between phases
400
A split-phase motor uses a resistive start winding (typically smaller wire) to get the motor turning. Identify the type of motor shown. [Figure: qr2 split phase]
Split-phase
400
What provides a connection to a stationary circuit by riding against a rotating component?
Brush
400
Identify the three DC motor starting circuits labeled A, B, and C. [Figure: qr3 dc start circuits]
A = series; B = shunt; C = compound
400
The function of an OCPD is to protect branch-circuit conductors, control equipment, and motors from damage caused by a(n) __________.
Overcurrent
400
Look at this damaged stator winding photo. What failure mode does it show? [Figure: qr3 stator overload]
Winding damage due to overload
600
What is the purpose of the centrifugal switch in a split-phase (or capacitor-start) motor after the motor accelerates?
Disconnect the start winding (and start capacitor, if used) at full-load speed *
600
Which DC motor has its field wired both in series and in parallel with the armature?
Compound-wound
600
Name the braking method where braking energy is dissipated as heat in a resistor after the motor is reconnected to act as a generator when turned off.
Dynamic braking *
600
How many overcurrent protective devices are required for all 3-phase circuits?
Three
600
This stator photo shows single-phasing damage. Is this a wye-connected or delta-connected winding pattern? [Figure: qr3 stator wye singlephase]
Wye-connected (single-phased)
800
Match each letter on the single-phase motor cutaway to its part name. [Figure: qr2 1ph parts]
A = endbell; B = capacitor; C = rotor; D = bearing; E = shaft; F = fan; G = stator
800
Identify the three DC generator types labeled A, B, and C in the illustration. [Figure: qr3 dc gen types]
A = shunt-wound; B = compound-wound; C = series-wound
800
What alignment method is shown in the illustration (two dial indicators on opposing sides of the coupling)? [Figure: qr3 reverse dial]
Reverse dial (rim) alignment
800
What is an inverse-time circuit breaker designed to do?
Trip after a delay based on overload severity
800
What instrument detects insulation failure on wires by measuring resistance under high-voltage test conditions?
Megohmmeter *
1000
Typical applications of capacitor motors include fairly hard-to-start loads such as refrigerators, air conditioners, compressors, and some power tools. Identify the motor type shown. [Figure: qr2 cap start run]
Capacitor start-and-run
1000
Which DC motor type has the field connected in parallel with the armature and is known for the best speed regulation? (Bonus: which type produces the highest starting torque?)
Shunt (best speed regulation); series (highest starting torque)
1000
In this dynamic-braking illustration, what is the purpose of the shunt (load) resistor across the armature? [Figure: qr3 dynamic brake resistor]
Provides a path for generated current so braking energy dissipates as heat
1000
What condition causes current to rise hundreds of times higher than normal at a very fast rate?
Short circuit
1000
On this split-phase motor ohmmeter check diagram, what does a reading of 0 Ω between the tested points indicate? [Figure: qr3 ohmmeter splitphase]