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ATT TEST 10 NEWEST TEST 2025 | ALL QUESTIONS
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TEST | VERIFIED ANSWERS
What is the rpm output of a prime mover that has a radius of 5 inches and is driven by a shaft at 4000 rpm with a radius of 3 inches? --------- CORRECT ANSWER----------------- 2400 What type of motion do nearly all position generators produce? --------- CORRECT ANSWER-----------------Circular What is the weight that one horsepower can lift one foot in one second? ---- -----CORRECT ANSWER----------------- 550 What type of resolver operates as a potentiometer? ---------CORRECT ANSWER-----------------Resistive What type of resolver operates as a transformer with a movable primary coil? ---------CORRECT ANSWER-----------------Inductive What determines the electrical output of a resistive position sensor? --------- CORRECT ANSWER-----------------The amount of resistance between the wiper and output Which figure describes 1, two,3 dimensional position? ---------CORRECT ANSWER-----------------look at figure
What term describes the location of an object with respect to a reference? - --------CORRECT ANSWER-----------------Position How does an encoder position sensor operate? ---------CORRECT ANSWER-----------------By sensing a code printed on the wheel In a inductive position sensor, what is the position of the primary and secondary coils for a maximum negative output? ---------CORRECT ANSWER-----------------look at figure How does an increment position sensor operate? ---------CORRECT ANSWER-----------------By counting the number of marks from the reference If a driven shaft is rotated at 2500 rpm for 0.05 seconds with a radius of 2 inches, how far does a 2 inch prime mover travel? ---------CORRECT ANSWER-----------------26.17 inches Which formula does not represent power of a prime mover? --------- CORRECT ANSWER-----------------(2π)(r)(rpm/60)(Time) What type of position sensor uses a wheel attached to the primer mover or connected to a moving object? ---------CORRECT ANSWER----------------- Digital
What determines the electrical output of a linear inductive position sensor? ---------CORRECT ANSWER-----------------The total induced voltage across series opposing fields What type of resolver is a linear voltage differential transformer? --------- CORRECT ANSWER-----------------Linear Stabilization is reached as the _______ reduces the overshoot of the signal. (PID) ---------CORRECT ANSWER-----------------derivative control mode The _______ control reduces overshoot. ---------CORRECT ANSWER------- ----------PD The _______ is the actual operating parameter or actual measured value. - --------CORRECT ANSWER-----------------process variable The _______ control reaches the set point value but degrades rise time. --- ------CORRECT ANSWER-----------------PI What control compensates for a changing value and inhibits rapid changes in the output value? ---------CORRECT ANSWER-----------------Derivative
What is the condition which indicates that the values of a circuit have settled and tend to remain constant? ---------CORRECT ANSWER------------- ----Steady-state Which control system provides a fast rise time, minimal overshoot, and quick response to outside influences? ---------CORRECT ANSWER----------- ------PID This schematic represents what type of rotating machine? --------- CORRECT ANSWER-----------------Separately excited DC generator How is a pulsating DC output eliminated in DC generators? --------- CORRECT ANSWER-----------------Using a multiple-loop armature What part of a motor allows reversing the magnetic poles in the rotor? ------ ---CORRECT ANSWER-----------------Commutator and brushes What principle of magnetism allows a generator to power its own stator windings and still generate an output voltage? ---------CORRECT ANSWER-----------------Retentivity In a generator, when the armature rotation is parallel to the stator magnetic field, what is the output voltage? ---------CORRECT ANSWER----------------- zero
What principle of magnetism do motors operate on? ---------CORRECT ANSWER-----------------Attraction and repulsion In the motor's voltage source circuit, what is the purpose of U1? --------- CORRECT ANSWER-----------------Difference amplifier In a motor, it is important to know that the starting current _______ --------- CORRECT ANSWER-----------------is higher than the running current. What principle of magnetism do generators operate on? ---------CORRECT ANSWER-----------------Passing a conductor through a magnetic field produces voltage How do you troubleshoot an automatic speed control circuit in a motor- generator set? ---------CORRECT ANSWER-----------------Signal tracing circuits What is the primary difference between a DC motor and DC generator? ---- -----CORRECT ANSWER-----------------The power source to the rotor is replaced in a generator with a load. In U1, if the non-inverting input voltage remains constant and the inverting input voltage increases, what happens to the output voltage? --------- CORRECT ANSWER-----------------Decreases
What principle of magnetism allows the use of electromagnet stators? ------- --CORRECT ANSWER-----------------Passing a current through a conductor produces a magnet What level of voltage is produced in an AC generator when the armature movement is parallel to the stator field? ---------CORRECT ANSWER--------- --------None In the revolving-field generator, there are no sliding contacts in the _______ ---------CORRECT ANSWER-----------------AC output circuit. In a Delta connected alternator, the line voltage equals the _______ --------- CORRECT ANSWER-----------------phase voltage In three-phase alternators, the windings are connected in either a Wye or _______ configuration. ---------CORRECT ANSWER-----------------Delta An AC generator is also known as a/an _______ ---------CORRECT ANSWER-----------------alternator. The principle of _______ is used for all motors and generators --------- CORRECT ANSWER-----------------magnetism In a Wye connected alternator, the line voltage is equal to _______ --------- CORRECT ANSWER-----------------phase voltage x 1.
What are the two basic components of a motor? ---------CORRECT ANSWER-----------------Poles and armature What is motor efficiency? ---------CORRECT ANSWER-----------------Ratio of output power to input power. If a motor is supplied 2500 watts of electrical energy, how much horsepower would it supply? ---------CORRECT ANSWER-----------------3. hp Mechanical power is defined in terms of _______ ---------CORRECT ANSWER-----------------horsepower. Inefficiency means the _______ ---------CORRECT ANSWER----------------- input is much greater than output. 100% efficiency means the _______ ---------CORRECT ANSWER------------- ----input power equals output power. When is torque maximum? ---------CORRECT ANSWER----------------- Locked condition Efficiency is measured as a _______ ---------CORRECT ANSWER------------ -----percent.
Electrical power is defined in terms of _______ ---------CORRECT ANSWER-----------------watts. CEMF and speed are _______ ---------CORRECT ANSWER----------------- proportional. If a motor is producing 1.5 hp, how much electrical power is it absorbing? (Assume no internal losses.) ---------CORRECT ANSWER----------------- 1119 W What does CEMF stand for? ---------CORRECT ANSWER----------------- Counter Electromotive Force As CEMF increases, what happens to conductor speed and torque? --------- CORRECT ANSWER-----------------Speed increases, torque decreases 1 horsepower equals how many watts? ---------CORRECT ANSWER--------- -------- 746 What is the efficiency rating of a theoretically "perfect" rotating machine? --- ------CORRECT ANSWER-----------------100% What is the rate of acceleration? ---------CORRECT ANSWER----------------- 4 ft/s/s
If the sensor holes were moved closer to the center of the disk but the same number of holes were used, at a given rpm, _______ --------- CORRECT ANSWER-----------------D is decreased so V would decrease. An rpm detector circuit with an F/V converter chip uses a disk with 100 marks/revolution and has a conversion factor (CF) of 2 V / kHz. Each 0. volts out of the chip represents _______ rpm. ---------CORRECT ANSWER- ---------------- 60 What is the velocity from point B to point C? ---------CORRECT ANSWER--- --------------8 ft/s What is motion? ---------CORRECT ANSWER-----------------A change in distance per change in time Which is not a popular motion sensor used in industry? ---------CORRECT ANSWER-----------------Photo Inductor In an F/V converter, the ratio between the input frequency and the output voltage is known as the _______ ---------CORRECT ANSWER----------------- conversion factor. For measuring rpm on a spinning shaft, the distance (D) between the sensing edges is _______ ---------CORRECT ANSWER----------------- unimportant.
If the number of sensing holes were doubled from 16 to 32, for a given rpm, the pulse train _______ ---------CORRECT ANSWER-----------------Tcycle would decrease to 1/2. What happens to velocity during acceleration? ---------CORRECT ANSWER-----------------Increases Acceleration is a change of _______ ---------CORRECT ANSWER------------- ----velocity in time. For calculating the velocity of the disk holes at various rpm values, the radius to the center of the holes and the distance between the holes are used to solve for _______ ---------CORRECT ANSWER-----------------runout rate. The most common motion detectors convert motion into _______ --------- CORRECT ANSWER-----------------frequency. An electrical differentiator circuit will sense a/an _______ voltage and disregard _______ values. ---------CORRECT ANSWER----------------- changing, absolute What are the two principle factors of motion? ---------CORRECT ANSWER-- ---------------Distance and time
To isolate the controlling circuitry, one must check the input to the circuit and the _______ ---------CORRECT ANSWER-----------------output from the circuit. To isolate the controlling circuitry, one must check the output from the circuit and the _______ ---------CORRECT ANSWER-----------------input to the circuit. Human error in troubleshooting could be related to _______ --------- CORRECT ANSWER-----------------motor parameters. equipment setup. input signals. The first step of the troubleshooting procedure is to _______ --------- CORRECT ANSWER-----------------recognize the problem. What is another name for a position generator? ---------CORRECT ANSWER-----------------Prime mover The _______ is the optimum operating parameter, or a reference to which an operator adjusts the process for optimum operation. ---------CORRECT ANSWER-----------------set point Which control system provides the poorest performance? --------- CORRECT ANSWER-----------------P
Proportional control uses an _______ as the means to increase rise time. -- -------CORRECT ANSWER-----------------adjustable gain A typical stepper motor has how many stator poles? ---------CORRECT ANSWER----------------- 4 If a stepper motor has 6 stator poles and 100 rotor nodes, what is the PPR of the motor? ---------CORRECT ANSWER----------------- 600 What type of rotor does a stepper motor use? ---------CORRECT ANSWER- ----------------(an) Permanent magnet What is a valid reason for using two-phase energized step patterns? --------- CORRECT ANSWER-----------------Smoother motor action A stepper motor is classified as a/an _______ motor. ---------CORRECT ANSWER-----------------incremental How are a stepper motor and AC motor similar? ---------CORRECT ANSWER-----------------Frequency of input waveform determines speed of motor. If a stepper motor has 6 stator poles and 100 rotor nodes, what is the value of one step (in degrees)? ---------CORRECT ANSWER-----------------0.
What is the purpose of the counter in a stepper motor's circuitry? --------- CORRECT ANSWER-----------------Determines CW or CCW motor rotation Which circuit in a stepper motor system develops the proper sequence of energizing the stator coils? ---------CORRECT ANSWER----------------- Controller What is the sequence of energizing the stators for a two-phase energized CCW pattern? ---------CORRECT ANSWER-----------------AB', A'B', BA', AB What is the sequence of energizing the stators for a one-phase energized CW pattern? ---------CORRECT ANSWER-----------------A, B, A', B' What is the term used to describe the number of degrees that a stepper motor rotates for each input pulse? ---------CORRECT ANSWER--------------- --Step Which circuit in a stepper motor system develops the power necessary to energize the stators? ---------CORRECT ANSWER-----------------Driver What type of signal turns Q1 ON? ---------CORRECT ANSWER----------------
If a stepper motor operates in the Step mode but does not operate in the Run mode, what is the probable faulted area? ---------CORRECT ANSWER-----------------Oscillator circuit Which two rates must the pps not exceed? ---------CORRECT ANSWER----- ------------SR and EFSS What is the purpose of D2 in the driver circuit? ---------CORRECT ANSWER-----------------Prevents damage to Q What level is on top of D2 when Q1 is ON? ---------CORRECT ANSWER---- -------------LOW Which formula calculates rpm of a stepper motor? ---------CORRECT ANSWER-----------------pps times 60 times step divided by 360 What is the following circuit called? (stepper controller) ---------CORRECT ANSWER-----------------Ramp up-down circuit Given the following stepper motor with a coil activation sequence of QA to QD, what direction will the rotor rotate? ---------CORRECT ANSWER--------- --------Clockwise What is the simplest type of controller? ---------CORRECT ANSWER---------- -------Full-step single-phase
