Chapter Questions
Selsyn transmitters and receivers resemble __________a. repulsion-induction motors.b. three-phase, two-pole induction motors.c. three-phase, four-pole induction motors.d. synchronous machines.
When the primary excitation circuit is closed, AC voltage is impressed on the __________a. transmitter and receiver primaries.b. transmitter rotor and the transmitter stator windings.c. transmitter rotor and the receiver stator windings.d. stator windings of both instruments.
A differential selsyn unit differs from a selsyn transmitter or receiver in that it requires __________a. three-phase power for excitation.b. an AC line connection to the stator winding.c. DC on the rotor winding.d. three connections to the rotor winding.
If the rotors of the two selsyn units in a selsyn-indicating system are in exactly corresponding positions, the current in the secondary winding is __________a. within quadrature with the primary current.b. in phase with the primary current.c. zero.d. less than the normal primary current.
Selsyn units are also referred to as __________a. synchros.b. induction motors.c. wound-rotor motors.d. all of the above
The stator of the transmitter is directly connected to the stator of the receiver unit when a differential is not used. __________a. trueb. false
In the transmitter and receiver system, the AC excitation is applied to the __________a. stator winding.b. stator and the rotor windings.c. rotor winding only.d. none of the above
Cite several advantages of a selsyn system.___________________________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
The purpose of a stepper motor is toa. provide incremental steps of motion.b. provide steps of rotation that are imperceptible.c. create a vertical motion rather than a rotational motion.d. create a stair-step output from the controller.
A synchronous Servos usesa. wound rotors for rotor construction.b. PM rotors.c. shaded pole rotors.d. squirrel-cage rotors.
Asynchronous Servos usea. wound rotors for rotor construction.b. PM rotors.c. shaded pole rotors.d. squirrel-cage rotors.
When a Servo motor is slowing down, the load inertia sometimes causes the motor to spin faster than desired. This is calleda. negative torque.b. over-speed torque.c. regenerative torque.d. dynamic braking inertia.