Motor Controls Level 3 Practice Test

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• Which statement correctly pairs the type of signaling with its typical connection configuration?
• When two or more thermocouples are connected in which arrangement to increase the output voltage from the sensor, the connection is referred to as a thermopile.
• The rating used to specify environmental protection for VFD enclosures is typically called what?
• Which type of manufacturing is described as the production of durable goods such as automobiles and refrigerators?
• PNP transistor output sensors are described as which type of current devices?
• What is the slip value for a synchronous motor at its operating speed?
• Which statement is true about constant temperature and calorimetric sensors?
• Which type of manufacturing produces consumables such as food, gas, paint, and chemicals?
• In which topology are all network devices connected to a central network media or cable identified as the backbone?
• Which statement best describes modular PLCs?
• A signal can be used to control the speed of a motor, determine the position of a valve, or indicate the level of a tank as it fills. What type of signal is this?
• Motor driven proportional control valves are generally slower to operate than pneumatic control valves.
• Which signal flow topology could include linear, divergent, or convergent paths and contains switches that can change the flow of the signal?
• Re-torquing is a good procedure to use to check the status of terminals that are held in place with bolts or screws.
• A 10-foot-tall tank uses a transducer that measures the liquid level with a 1-5 VDC signal monitoring the top 8 feet. If the transducer reads 3.5 VDC, how many feet of water are in the tank?
• A smart device's self-diagnostic capability assists in what?
• What is the term for the connection of two or more thermocouples in series to increase output voltage?
• The PC and PLC architectures share similarities such as a motherboard, memory, expansion slots, and which component?
• A specification for an Ethernet network calls for a 100BaseT system. What type of cable is used for this network?
• Proportional control valves are always controlled with an electronic voltage or current signal.
• Open-loop motor control is characterized by which of the following?
• For a stepper motor with an angular resolution of 1.8° per step, how many discrete steps are needed for a full 360° rotation?
• Is it important to understand and follow proper precautions and handling procedures to avoid ESD damage to solid-state devices?
• To check if a rheostat is working properly, test each tap for a different resistor value using which instrument?
• The ? motor is a 3-phase motor in which the rotor turns at the same speed as the magnetic field of the stator.
• What type of flow meter requires particles in the fluid to reflect signals back to the flow sensor?
• What component do solid-state drives not use, resulting in energy not wasted as heat?
• What is the temperature range a Type J thermocouple can sense?
• In a fixed and modular PLC, which interfaces provide the link between the PLC and external devices such as lamps, motor starters, and solenoids?
• What type of connector is required to connect the communications cable to monitor or program the VFD with an external PC?
• Speed and ? are two physical quantities that must be controlled in a motor drive.
• In the tank measurement example, which voltage represents 8 feet of water?
• A load cell is a sensor used to measure which physical quantity?
• Tachometer and encoder monitor which motor parameter?
• Which type of module connects to sensors that measure process conditions in a modular PLC?
• A typical hybrid stepper motor has how many rotor teeth?
• Which statement best describes ramping in DC drives?
• What is a key benefit of avoiding premature tests during bracketing analysis?
• Rotary potentiometer position sensors detect the angular or rotational position of a shaft.
• Which device provides feedback voltage proportional to motor speed, used in speed control?
• Which trigger produces a deadband, preventing output switching ON and OFF as the input crosses the threshold?
• Which statement describes the devices used to provide speed reference signals in a closed-loop speed control system?
• What parameter does a VFD vary to control the speed of an AC motor?
• The speed of a DC motor is primarily controlled by adjusting which parameter?
• Which braking method decelerates the motor faster?
• NPN transistor output sensors are described as which type of current devices?
• The motor that can be started manually with a rheostat is which type?
• Generally, which type of signals with a very low source resistance are less sensitive to electrical noise from welders and electric motor starters?
• RTDs and thermistors are temperature sensing devices that exhibit a change in what, which is dependent upon temperature?
• The statement 'It is important to make and break contacts as quickly as possible to extinguish the arc promptly and to extend the life of the contacts and contactor' is true. Which option best represents this assessment?
• Lower initial cost and easier installation are two advantages of a(n) ? motor control system.
• The four listed circuit types AC/DC, DC current-sinking, DC current-sourcing, and TTL are the four most common types of which circuits used in controller input modules?
• Are all VFDs configured and programmed the same way?
• A ? network connects enterprise networks together.
• During startup, most problems are identified and corrected in which area?
• Factory enclosures for VFD installations should have what rating appropriate to the level of protection for the installation?
• A device that receives one type of energy and converts it to another type of energy and generally includes a sensor and a transmitter is called what?
• Regenerative braking returns regenerated power to which of the following?
• Which type of network media is capable of transferring data up to 100 Gbps?
• What term describes the maximum torque a stepper motor can withstand without moving when the stator is de-energized?
• Which network interconnects industrial devices such as limit switches, photoelectric sensors, valves, motor starters, process sensors, and operating interface devices via a single network?
• Cable terminators are required on both ControlNet and DeviceNet networks to prevent reflections. This statement is true or false?
• Which device is described as an electronic assembly that connects an individual device to the network?
• A limit switch is an example of a discrete signal.
• What is the rapid flow of electrons between two bodies of unequal charge called?
• Transducers convert a variable such as temperature, position, flow, or pressure into what type of signal used by the control system?
• Which type of flow sensor uses a bluff body placed in the fluid flow to produce whirlpools or eddies?
• Most DC motor contactors consist of how many sets of contacts?
• The resistor value used to interface a 4-20 mA loop with a 1-5 VDC device is 250 ohms. Which option matches this value?
• External devices such as lamps, motor starters, and solenoids are examples of which PLC I/O category?
• What is the full-scale voltage of the 1-5 VDC signal used to monitor the top 8 feet of water in the tank?
• The ? windings in a synchronous motor dampen speed fluctuations and allow the synchronous motor to operate as an induction motor until synchronous speed is achieved.
• At which step in a funneling analysis troubleshooting procedure are tests generally limited to a single unit in the system block diagram?
• Before installing a VFD, the equipment manual and the labels on the VFD are two sources of information to consult. Which statement is true?
• Analog devices connected using a voltage type analog signal are connected in what?
• Which load type is classified as constant horsepower loads?
• Efficient troubleshooting of a network control system requires knowledge of the vendor's system software program.
• Which type of network links multiple enterprise networks across broader geographic areas, often using public links?
• In which PLC configuration are the processor, power supply, I/O modules, and communication modules all housed in a single unit?
• PLC systems are used to control two classifications of industrial electrical systems. Which statement best describes them?
• The motor connected to the VFD can be run in the reverse direction?
• In modular PLC discrete outputs, which type provides mechanical contact switching?
• Based on the new information, where should the next test point be?
• Which section of a DC drive is capable of controlling the motor direction?
• For a stepper motor with an angular resolution of 0.72° per step, how many steps are required for a full 360° rotation?
• In a modular PLC, which modules provide the link between the PLC and external devices that measure process conditions?
• Regenerative braking returns regenerated power of a DC motor back to the power source.
• Which technique is described when brackets are widely separated and tests tend to be more general in nature?
• Which device is described as 'Device used to segment LANs to balance network traffic and to provide data filtering for security purposes'?
• What is the effect of the blowout coil on the arc when a contact opens?
• The MicroLogix 1000 controller by Allen-Bradley is a stand-alone device and all I/O can be connected to its main chassis. Which option is true?
• A common type of sensor used to measure weight is a ____ sensor.
• Which two devices are used to monitor the speed of the motor for feedback in a DC drive?
• Convergent topology describes multiple inputs converging into a single path. Which option best completes this statement?
• Which technique divides troubleshooting into two categories focusing on power paths and information paths?
• Which statement correctly characterizes a key difference between discrete control valves and proportional control valves?
• A PLC is an industrial what designed to control manufacturing machines and systems?
• Ramping works well for which loads?
• What is the purpose of opto-isolation in controller modules?
• Which PLC component provides the mechanical support for the modules?
• Most DC motor drives detect and display common circuit and/or fault numbers to help identify problem conditions.
• Controller input and output modules have opto-isolation to prevent noise and operational problems. True or False?
• True or False: By bracketing and funneling analysis procedures, pointless tests are avoided and wasted effort is eliminated.
• Amortisseur windings in a synchronous motor help start by temporarily behaving like an induction motor before reaching synchronous speed.
• A tachometer/generator provides a feedback voltage that is directly proportional to which motor quantity?
• What DC control voltage is used to control the speed of the motor connected to the VFD?
• The DC control voltage used to control speed is measured in which units?
• A limit switch is an example of a(n) signal.
• The ? motor converts electronic digital pulses into mechanical rotational steps.
• What type of signal is continuous, varying from a minimum to a maximum value?
• What type of signal has only two states: ON and OFF?
• If a normally open discrete contact is connected to turn the motor on and run forward, to which two terminals would you connect the contact?
• To monitor or program the VFD from a PC, which connector is used?
• What is the common term for a graphic terminal used to interact with an industrial network?
• Which statement about field devices in relation to PLC hardware is true?
• Devices such as switches and sensors, motor starters, pilot lights, and solenoid valves connected to a PLC are identified as which type of devices?
• In a closed-loop control system, which term identifies the speed value that is compared with the actual speed to produce an error signal?
• Which network is described as an open standard for industrial networking?
• Which of the following is not an example of an analog signal?
• Feedback topology describes a path where the signal is returned to influence earlier stages. Which option best completes this statement?
• In a closed-loop control architecture, which component is primarily responsible for comparing the requested speed with the actual speed and generating an error signal?
• When stopping heavy loads without a brake, what happens due to inertia?
• Which term describes a device that takes an input analog signal and outputs an analog signal of potentially a different type or range?
• Which network is primarily used for process automation and includes process variables, real-time control, and diagnostics?
• A network that acts as a data highway within an enterprise network is called a ? network.
• A motor control system that uses a tachometer to control the speed of the motor is called a(n) ? system.
• In most modern servo motor controls, what has replaced servo amplifiers as the controlling system?
• What is the primary purpose of line reactors in VFD-powered systems?
• The self-diagnostic capabilities of smart devices are helpful when troubleshooting smart systems.
• Arc chutes typically absorb greater than 80% of the energy released during the interruption of current flow as the contacts open. This is described as:
• ControlNet is described as an open network standard, allowing any company to use it without licensing fees. This statement is true or false?
• A smart or intelligent device contains a solid-state circuit or chip that provides communication and diagnostic capabilities for the device.
• In synchronous motors, ? have two winding types, salient pole windings and amortisseur windings.
• Which type of servo motor is typically used in computer-related devices and CNC machines where starts and stops must occur quickly and accurately?
• Turbines and paddlewheels immersed directly in a process liquid are used to measure which quantity?
• Which network links branch offices and single mobile users to a local enterprise network or the Internet?
• AC, DC, and TTL are the three most common types of which circuits used in controller output modules?
• Which of the following can be used as programming devices to configure VFDs?
• Which drive software feature displays drive parameters such as voltage, current, frequency, speed, and power consumed?
• Allen Bradley's SLC500 and CLX5000 are which type of PLC systems?
• Which network type is used for process management including process variables, real-time process control, and diagnostics?
• When using a VFD, a motor's ramp-up speed can be adjusted to vary from a few seconds to more than how many seconds?
• Which element of both PC and PLC architectures handles processing tasks?
• Which type of servo motor is used for rapid positioning in industrial applications where low inertia is present?
• What is the primary function of the backplane in PLC systems?
• In PLC terminology, a stand-alone PLC is characterized by which of the following?
• In which topology are all network devices connected to a common device called a hub or switch?
• In a linear variable differential transformer, the secondary windings are connected in what arrangement?
• Opto-isolators for AC signals contain how many LEDs, and DC circuits contain how many LEDs?
• Modular PLC discrete output modules are available with solid state AC, solid state DC, and ? type outputs.
• Which statement about the blowout coil effects on arc behavior is accurate?
• The control set points of a VFD establish the speed, rotation direction, and stopping parameters for the motor.
• In a fixed and modular PLC, which interfaces provide the link between the PLC and external devices such as switches and sensors?
• In a system diagram scenario, when evidence shows utility power is present at the emergency generator while there is a reported loss of power, which bracket indicates the new area requiring inspection?
• Which of the following is true regarding electrostatic discharge (ESD) in electronics handling?
• Which statement best describes a switched path topology?
• A VFD operating without feedback from the motor is described as which control type?
• Which network permits all nodes on the network to simultaneously access the same data from a single source?
• Which topology is described by a signal splitting into two parallel paths after a single point?
• In which topology are network devices connected to a network media or cable, which is connected in a loop?
• 0-10 VDC, 4-20 mA, and 3-15 psi are examples of what type of signal?
• Which statement best describes closed-loop control?
• TTL stands for Transistor-to-Transistor Logic. This term describes which category of components?
• When the core of an LVDT is at the center position, the output voltage is zero.
• Discrete control valves are binary; they have how many states?
• When a synchronous motor is connected to 3-phase power lines in parallel with other AC motors with lagging power factor, the synchronous motor will ? the power factor of the circuit.
• Which type of PLC system manufactured by Allen Bradley allows multiple processors in the same chassis?
• In the tank description, what is the unmonitored portion of the tank height?
• In a servo system, which component within the controller is primarily responsible for driving the servo motor to the commanded position?
• Which type of analog signal can be used to not only control the speed of a motor, but also the direction of rotation of the motor?
• Which programming software feature monitors and displays the value of all drive and motor parameters in real time?
• What term denotes the number of degrees the motor moves per step?
• How many steps are there in the troubleshooting sequence?
• Which device is the central connecting device in a network, sometimes called a multiport repeater?
• A bourdon tube pressure sensor often uses an LVDT to sense position relative to the applied pressure.
• What type of device converts from one analog signal range to a different analog signal range when the values don't match?
• Block diagrams are used primarily to illustrate what?
• Which term describes focusing inspection on the most probable areas by progressively narrowing the search?
• Which modules in a control system are designed to have opto-isolation between field power and controller power?
• How many factory default speeds are available for this VFD?
• Which basic troubleshooting technique includes four levels of testing?
• The VFD is an example of what type of control?
• During dynamic braking, the motor operates as a DC generator after the main power is removed.
• True or False: To better understand abnormal operation, it is essential to first understand normal operation.
• In an LVDT, the secondary windings are connected in series.
• Which load type is classified as variable torque loads?
• In a solid-state DC drive, the section capable of varying speed above and below the base speed is the
• Three-phase motors typically have slip, which is the difference between rotor speed and field speed. What is the slip of a synchronous motor?
• The deadband in a trigger causes which of the following regarding output switching as the input moves around the threshold?
• Which troubleshooting technique is generally divided into two groups called power and information?
• Tachometer/generators and optical encoders are two types of devices generally used to provide speed reference signals in which speed control system?
• PLC programming is performed by which device or tool?
• True or False: A servo motor controller's described role includes receiving sensor signals, controlling the system, and sending signals to a PLC.
• In a 4-20 mA DC current loop, with a 250-ohm resistor connected in parallel to a 1-5 VDC relay, if the loop current is 12 mA, what is the relay input voltage?
• DC currents stay above the zero axis and maintain a constant current flow to the motor. This describes currents that are which of the following?
• Which device is NOT listed as a programming device for configuring VFDs?
• Which devices provide opto isolation between field device power and controller or motor drive system power?
• Where would you connect if converting to a closed-loop system by adding a 0-10 VDC analog source?
• Which network's acronym expands to Serial Real-time Communication System?
• SERCOS is an acronym for which phrase?
• What is the speed in Segment 2 of the profile?
• The ? motor is a position or motion correcting motor that is driven to a specific angular position as commanded by a control signal.
• Divergent topology describes a single input splitting into multiple outputs. Which option best completes this statement?
• Which load type is classified as constant torque loads?
• In motor stator temperature monitoring, thermocouples are faster to respond than RTDs.
• What term is used to describe a PLC where all essential sections are housed in one unit?
• A network consisting of intelligent machines connected together in a company building or group of company buildings is called a(n) ? network.
• Which of the following is NOT a standard DC contactor coil voltage rating?
• What device is installed on power lines feeding VFDs to lessen harmonics?
• During operation of a DC rheostat motor starter, the resistance is increased in the field winding and reduced in the armature until the motor reaches full speed. Which option describes this change?
• Thermocouple transmitters generally produce 0-15 mA output signals.
• The magnetic blowout coil produces a magnetic field between the breaking contacts that forces the arc up, increasing the length of the arc and causing it to dissipate faster. Which coil is this?
• Which IEC standard programming language most closely replicates traditional magnetic motor control diagrams?
• In the troubleshooting sequence, the first how many steps are repeated as often as necessary until the fault is located?
• Regenerative braking decelerates the motor faster than dynamic braking.
• What term describes a communication system where two or more intelligent machines share information?
• Which formula relates current, resistance, and voltage in a simple resistor circuit?
• Arc suppression components are designed to absorb most of the interruption energy. Which option best describes this function?
• Linear topology describes a signal path that travels through a sequence of stages with no branching. Which option best completes this statement?
• Linear potentiometer position sensors sense the linear motion of an object.
• Which materials are required for Type J thermocouples?
• A 1-5 VDC analog device can be used in a 4-20 mA DC loop circuit if a 250 ohm resistor is connected across the input to the device and the 4-20 mA DC current is routed through the resistor. The current signal produces the proper voltage to operate the 1-5 VDC device. (True/False)
• In a configuration that uses an external analog 0-10 VDC input, which connector is designated to receive that signal?
• The servo motor controller not only includes an amplifier that drives the servo motor, but also contains circuitry to receive sensor signals, control the system, and send signals to a PLC. True or False?
• To begin troubleshooting a VFD, four sections of a drive circuit must be inspected: input devices, output devices, programming configuration, and VFD internal components. Which option lists these four sections?
• What is the term used to identify the speed change in Segment 3?
• Convert 88°C to Fahrenheit.
• Analog devices connected using a current loop analog signal are connected in what?
• Which device is typically immersed in a process liquid to measure flow?
• All DeviceNet cable systems include device power and data integrated into a single cable system. Which network is this referring to?
• In an LVDT, the primary winding is connected to what type of voltage?
• Modular PLCs are built by selecting components that fulfill the requirements for the control application and installing them into the rack or chassis. This statement is which of the following?
• The Serial Real-time Communication System network uses which topology?
• For long-distance analog control wiring, which signal type is preferable?
• Which device coordinates multiple servo axes by communicating with a PLC in a typical system?
• Thermocouples are temperature-sensing devices that produce what type of signal when the temperature increases?
• What is the voltage level of a Class 1 solid-state device that may cause potential damage?
• Which type of motor is generally less expensive and requires less maintenance?
• The SERCOS network uses which topology?
• What type of flow meter depends upon the twist of the tube containing the flowing fluid to sense flow rate?
• Which topology involves two independent inputs merging into a single output?
• Which troubleshooting technique uses external markers to identify the portion of the block diagram in which the fault exists?
• What term refers to the maximum number of steps the motor makes in one second?
• Most new or upgraded DC systems use which starting method?
• The standard coil voltage ratings for DC contactors are 12, 24, 48, 120, and which value?
• Which motor is driven to a commanded angular position using feedback control to achieve precise motion?
• Cable terminators are required on ControlNet and DeviceNet networks to prevent reflections. Which statement best describes this?
• Which statement correctly describes how analog signals relate to a variable's value?
• Proportional control valves respond to an analog signal and adjust flow over which range of the valve’s capacity?
• Which statement about speed control in DC drives is true?
• Which section of solid-state DC drives supplies the DC voltage to the motor?
• For a stepper motor with an angular resolution of 90° per step, how many steps are required to complete a 360° rotation?
• The section that handles speed commands and logic in a DC drive is the
• Which motor is typically used for precise open-loop positioning by stepping with digital pulses?
• With the same scenario but additional evidence that there is no outage to manufacturing or data equipment blocks, which bracket indicates the new area for testing?
• Ramp-up in a VFD-controlled motor refers to:
• In an SLC500 PLC system, the total number of modules and I/O points is limited to what can be installed in a single chassis.
• When connecting an alarm light to the 02 terminals, the alarm would be powered how?
• Which device documents industrial and commercial process data as analog output?
• Which type of signals provide a continuous indication of the value or position of the variable being monitored?
• When performing maintenance with the motor off, a visual inspection should include checks for excess dirt accumulation, burns, or damaged starter components.
• Which statement is true about ultrasonic flow meters?
• What are the three basic maintenance categories for a VFD?
• Which coil in a DC contactor is specifically responsible for the arc blowout effect?
• During the start of a DC motor using a rheostat, which statement about current is correct?
• When troubleshooting a VFD, the four sections to inspect are input devices, output devices, programming configuration, and VFD internal components. Is this statement correct?
• Which section of a solid-state DC drive is capable of varying the motor speed above and below the motor base speed?
• Which of the following is an example of a field device connected to a PLC?
• Which technique uses markers to isolate fault location within the diagram?
• In a closed-loop speed control system, the set point speed value is the:
• The physical path over which electrical or optical signals travel from one device to another is called the ?.
• What is the term for a sensor output that sinks current from the load when active?
• The LVDT output represents what physical quantity?
• During dynamic braking, the motor operates as which device after the main power is removed?
• In a field device powered sensor, which component provides optical isolation to prevent noise transfer?
• DC drives use which method to smoothly accelerate and decelerate the motor?
• RTDs and thermocouples are typical analog sensing devices that measure what in a process?
• Which troubleshooting technique is a set of rectangles used to identify the parts of a system?
• Which statement about understanding operation is correct?
• How many DC motor wiring configurations are possible?
• What does LVDT stand for?
• Troubleshooting techniques are proven procedures that provide a structure for the troubleshooting process.
• Which IEC programming language is commonly used to implement control diagrams in motor control applications?
• If the emergency power generator is tested and shows no faults while loaded, what does this indicate about the generator?
• The braking resistor in dynamic braking is connected to the armature leads.
• Constant temperature and calorimetric sensors are types of which flow sensors?
• What term describes the maximum torque a stepper motor can withstand without moving when the stator is energized?
• Motor control systems that control motor speed without feedback data for torque or speed are called ? control systems.
• Which type of pressure sensor uses a second process pressure as a reference instead of atmospheric pressure?
• Stepper and servo motors are two special types of motors that require special input/output modules in a PLC system.
• What type of device has one type of analog signal as an input and produces another type of analog signal as an output?
• Which displacement sensor is widely used for precise linear measurement and uses a transformer principle?
• What is the term used to identify the speed change in Segment 1 of a typical speed profile?
• Which technique focuses on mapping the flow of power and information through a system?
• Which list accurately identifies the four parts of a closed-loop motor control system?
• What is the highest level of factory floor network architecture that provides an information layer for enterprise-wide data collection and program maintenance?
• Which PLC component is a printed circuit board that delivers power to the modules and provides the data bus for exchanging data between modules and the CPU?