Eksamen Flashcards

Question

QUESTION 25 What is the purpose of the brushes in a DC motor Cool the rotor Transfer electricity to the rotor Dampen the acustic noise Dampend the EMI

Answer 1

QUESTION 25 What is the purpose of the brushes in a DC motor Cool the rotor Transfer electricity to the rotor !!!!! Dampen the acustic noise Dampend the EMI

Answer 2

QUESTION 26 What is typical wearing part of a DC motor The magnets The axle The isolation material The brushes !!!!!

Answer 3

QUESTION 27 Can a stepper motor run directly from a DC source No !!!!! Yes Yes, but very slow Yes, but only at full speed

Answer 4

QUESTION 28 What is the typical benefit of a stepper motor High speed High torque density !!!!!! Low noise Very linear speed

Answer 5

QUESTION 29 What is the typical voltage range of stepper motors 230-480V 115-230V 5-80V !!!!!! 0-3V

Answer 6

QUESTION 30 Why is the asynchronous motor so common High precision Very compact Low cost !!!!! Very efficient

Answer 7

QUESTION 31 How is the magnetic field typically generated in synchronous motors By injecting AC current into the supply By the rotational force By permanent magnets !!!!!! It is not needed

Answer 8

QUESTION 32 What are the main parts of a frequency inverter (converters?) Rectifier + DC-bus Rectifier + DC-bus + Inverter !!!!!! Inverter + DC-bus + Inverter Solid state relay

Answer 9

QUESTION 33 What is mandatory in a closed loop servo motor system Stepper motor A common DC-bus A motor with permanent magnets Some sort of encoder feedback from the motor !!!!

Answer 10

QUESTION 34 What is the difference between incremental- & absolute encoder Incremental encoder is the most precise Absolute encoder is the most precise Incremental is best for high speed applications Absolute encoder can remember the position after power interruption !!!!!!

Answer 11

QUESTION 35 Which signal type does a resolver deliver High voltage (>24V) Analog !!!!!! TTL pulse train RS485 protocol

Answer 12

QUESTION 36 What is the definition of inertia mismatch in motor design The quality of the mechanical coupling The gear ratio between the load & motor The load inertia compared to the motors rotor inertia !!!!! The weight of the motors rotor divided by the motors torque

Answer 13

QUESTION 37 In which PLCopen state is the MoveAbsolute executed? Standstill Continuous Motion Discrete Motion !!!!!! Running Motion

Answer 14

QUESTION 38 How is the master axis affected to the function 'gear in' from a slave axis? Master follows the slave Master waits for the master and slave speed to match Master axis must always be faster than the slave Master axis is not affected at all !!!!!

Answer 15

If we have a mechanical non-periodic system, where 5 motor revolutions equals to 1 revolution on the output shaft of a gearbox, and 1 revolution of the output shaft of the gearbox gives a mechanical movement of 15mm, and we want to achieve an application resolution of 0,01mm, then how should the motor_rev, units, periode and factor values be set in PLCopen? rev_motor = 5, units = 1500, period = 0, factor = 100 Answer: 331, 332 Datasheet - As said we have 5 motion revolutions for one revolution of the gearbox. This in turn moves the output movement 15mm. This is described as 15 units. We want a precision of 0,01mm. We then need to multiply the unit value by 100 (This is the factor), giving us a unit = 1500. The period is only used for periodic axis (e.g. a conveyor belt). At this value the position is reset and counts from 0 again. As this is not required here. The period is zero. rev_motor = 5, units = 150, period = 0, factor = 100 rev_motor = 50, units = 1500, period = 0, factor = 1000 rev_motor = 5, units = 1500, period = 0, factor = 1000

Answer 16

QUESTION 40 When does an axis enter state Standstill after a MC_Stop() command? When the MC_Stop.Done = TRUE When the axis speed is 0 When the MC_Stop.Done = TRUE and MC_Stop.Execute is set to false When the MC_Stop.Done = TRUE and MC_Power.Done = TRUE !!!!!!

Answer 17

QUESTION 41 PLCopen motion control function blocks either have an enable or execute input. What is the difference? Enable looks at the input level, where execute looks for a rising edge. !!!!! Execute looks at the input level, where enable looks for a rising edge. Enable needs to be tied to a variable and execute must be tied to a physical button. There is no difference.

Answer 18

QUESTION 42 From which PLCopen state, can an axis enter the Errorstop state? Only from the Aborting state From all states that perform a movement of the axis From any state - if the axis is powered on and homed From any state - If an error has occurred on the axis !!!!

Answer 19

QUESTION 43 Which of the following are inputs, that PLCopen all function blocks have? Axis reference and Enable/Execute !!!!! Axis reference and acceleration/deceleration Master and slave axis references Enable and execute

Answer 20

QUESTION 44 What happens if a PLCopen function block is called with execute input set TRUE for 1 scan, and then the execute input is set FALSE? The execution of the function block is aborted The function block gets stuck in a loop, and never finished the execution. The function block reports back an error ID. The function block is executing correctly - Output signals are only present for 1 scan after completion. !!!!!

Answer 21

QUESTION 45 What does it mean, If an axis is configured as a periodic axis? The PLCopen axis position will roll over, when the maximum value of the position datatype is reached (DINT 2^32). The PLCopen axis position will roll over and restart from the home position, every time the periodic position is reached - The axis scaling itself is overwritten by the axis period. Singleturn encoder motors are always periodic, multiturn encoders are non-periodic. The PLCopen axis position will roll over and restart from 0, every time the periodic position is reached - The axis scaling itself is not affected. !!!!!

Answer 22

QUESTION 46 What is the Position input on the MC_Home function block? It is what the position value will be set to, after a homing has been completed. This is the home position, and should always be set to 0. It is the home position, that is used exclusively when homing mode Direct is used. It is the physical value of the axis encoder in the home position. !!!!!!

Answer 23

QUESTION 47 What is the difference between Discrete and Continous movement types in PLCopen motion? Discrete movements happen in Synchronized Motion state, but only for the slave axis. Continous movements happen in Continous Motion state, and are movements that have no defined end, and will continue until stopped or interrupted by another movement. Discrete movements happen in Discrete Motion state, and are movements that have a defined end. Continous movements happen in Continous Motion state, and are movements that have no defined end, and will continue until stopped or interrupted by another movement. !!!!! Discrete movements happen in Discrete Motion state, and are movements that have a defined end. Continous movements happen in Synchronized Motion state, but only for the slave axis. Servo motors always operate in discrete movement, while frequency inverters always operation in continous movement.

Answer 24

QUESTION 48 What is the definition of lag error on an axis? Axis is in an error state, and cannot be started The difference between the set position, and the actual position !!!!! The axis is running uneven, a laggy motion. A set position has been requested, which is outside the period of a periodic axis

Answer 25

QUESTION 49 What runtime capabilites has Automation Runtime Real-time performance !!!!! Non deterministic execution Multi-threading system Real-time, non deterministic and multi-threading

Answer 26

QUESTION 50 What is the most important difference between Automation Runtime and Windows Input/output modules can be connected OPC-UA server Deterministic task scheduling !!!!! Windows cannot run on an industrial PC

Answer 27

QUESTION 51 What kind of service it not a standard part of the Automation Runtime? MySQL database !!!!! Web server FTP server OPC-UA server

Answer 28

QUESTION 52 What kind of PLC memory is used to store the values of PLC variables after a power failure? SRAM and FRAM SRAM DRAM !!!!! FRAM

Answer 29

QUESTION 53 What kind of PLC memory could be compared to RAM on a personal computer? SRAM DRAM !!!!! FRAM ROM

Answer 30

QUESTION 54 What kind of PLC memory is important if you mark a PLC variable as retained? SRAM or FRAM !!!!! Flash memory DRAM Cache memory

Answer 31

QUESTION 55 What kind of PLC memory is relying on a battery in the PLC? DRAM Flash memory FRAM SRAM !!!!!

Answer 32

QUESTION 56 Where is the PLC program saved when the PLC is not powered on? Flash memory !!!!! FRAM SRAM DRAM

Answer 33

QUESTION 57 What is a watch-dog on a PLC? It is a restart button on the PLC It is a service that monitors that the scheduler timing rules can be fulfilled !!!!! It is an interrupt service that the programmer can use. It is an I/O scheduler service.

Answer 34

QUESTION 58 What happens if you try to create an endless while loop in your PLC program? It uses all ressources on the PLC and leaves no time for other processes. It triggers a watch-dog after some time and the PLC goes to service mode !!!!! It is allowed to run endlessly, but only when the task is scheduled to run by the scheduler. The compiler will give you an error as it is not allowed.

Answer 35

QUESTION 59 What could be the best solution if you have a program that require real-time performance every 400 µs, but once in a while you have to do some heavy mathematical algorithms which takes more than 400 µs for the PLC to complete? Set task-class cycle time of 400us and a tolerance time at 0us Set task-class cycle time to 400 us and higher task class tolerance Get a better performing PLC. Split the program into two task classes !!!!!

Answer 36

QUESTION 60 What is idle-time? Time where the PLC is doing nothing !!!!! Time where scheduled tasks can be executed Time where the PLC is executing tasks that does not need to be scheduled Time where I/O scheduling is done

Answer 37

QUESTION 61 What would be a reason for choosing one of the graphical programming languages? Easy to troubleshoot by e.g. a service engineer or a technician. !!!! Gives a good overview of very large programs. Can easily be converted to high level languages if needed. Graphical languages are old school and will never be chosen for a new project.

Answer 38

QUESTION 62 Instruction List memory usage - Which statement is true? Instruction List uses a lot of memory, because it is a high level language. Instruction List uses a lot of memory, because you have to program many lines, even for simple tasks. Instruction List uses little memory, because it is a low level language. !!!!!! Instruction List only uses little memory if you avoid using labels.

Answer 39

QUESTION 63 According to the Ladder Diagram standard, what must be obeyed? You may not use power flows. You may not call functions or function blocks. You may not use contacts. You may not set a coil more than once in a program. !!!!!

Answer 40

QUESTION 64 Ladder Diagrams have a close resemblance with: High level programming languages. Electrical diagrams. !!!!!! Mathematical equations. Flow diagrams.

Answer 41

QUESTION 65 Is it possible to use loops in Structured Text? Yes, you can use loops like WHILE, FOR and REPEAT. !!!!! No, loops cannot be used, because it is a low level language. Yes, but you can only use the FOR loop. Yes, but you can only use WHILE and FOR loops.

Answer 42

QUESTION 66 What is the maximum value of an UINT variable? 127 32767 65536 65535 !!!!

Answer 43

QUESTION 67 What is the value of testVar if step = 6 (see example code in picture)? "testVar = 15;" "testVar = 20;" "testVar = 25;" The example code cannot be executed, because of programming errors.

Answer 44

QUESTION 68 What is the purpose of on a safe digital input module? To be able to detect short-circuit to supply To be able to detect short-circuit to ground To be able to detect short-circuit to other channels All of the above are correct !!!!!

Answer 45

QUESTION 69 What does "via safelogic" mean for a safety output? Only the non safe application controls the ouput states Only the safe logic application can control the output state !!!!! Both non safe and safe applications control the output state Output state is permanently on

Answer 46

QUESTION 70 Where is the safety code executed? Only in the PLC/CPU Both in the PLC/CPU and the SafeLogic Only in the SafeLogic !! - Safety koden bliver kompilet af to forskellige compiler, og kørt på 2 forskellige cpu’er, så det kan tjekkes om koden bliverkompileret ens og kørt rigtig. None of the above

Answer 47

QUESTION 71 What is the purpose of the self-tests of a safe digital output module? To be able to detect short-circuit to supply or ground !!- Den skal være I stand til at slukke for systemet selv I korte pulser. Hvis den ikke kan det, så er det fordi der er short-curcuit et sted. To be able to detect faults on the hardware itself To test the emergency stop hardware buttons status (pressed / not pressed) Only safe digital input modules are equipped with this type of test

Answer 48

QUESTION 72 Which of the following is not part of the safety response time? The time for the operator to react on an emergency situation !!!!! Signal processing time in the sensor Application processing in the safety PLC Time for the actuator to stop

Answer 49

QUESTION 73 What is openSafety? A co-operation between vendors of safety hardware A safe transfer protocol !! - kører på eksisterende field bus, normal vis power link, men ikke begrænset til det. A library with safety functions and functionblocks A programming tool for the safety application

Answer 50

QUESTION 74 What's the benefit of integrated safety? Increases the number of hardware modules that can be integrated in a system Increased reaction time of safety functions Gives a more flexible safety system with more opportunities than a traditional system !!!! Reduced over-all cost of the safety related part of a machine

Answer 51

QUESTION 75 What is the "discrepancy time" when talking safety? The processing time of the signal in the SafePLC The fieldbus network cycletime The SafeIO module execution time, i.e. the time it takes to set the output signal The maximum timedelay between individual signals in a 2-channel safety input - video 2. 18:07

Answer 52

QUESTION 76 Which command should be used if a machine should transist to PackML state Resetting? Start Restart Reset !!!! Execute

Answer 53

QUESTION 77 Which state comes after Resetting in the PackML state model? Idle !!!! Execute Stopped Ready

Answer 54

Holding / Held - Når der er noget internt der blockerer (mangler kapsler) Suspending / Suspended !!!- når der er noget eksternt der blokerer Blocking / Blocked - eksisterer ikke Completing / Complete - er kun til maskiner der kører periodiske tjek. Når maskinens periode er færdig.

Answer 55

QUESTION 79 An operator presses the emergency stop button. Which state should my machine go into? Stopping / Stopped Terminating / Terminated Halting / Haulted Aborting / Aborted !!!!!

Answer 56

QUESTION 80 What does the abbreviation SC mean in PackML? State Clearing State Complete !!!!! State Continuously Status Counting

Answer 57

QUESTION 81 Which state type is state CLEARING? Acting !!!!! Waiting Dual Running

Answer 58

QUESTION 82 Which of the following is not a mode defined in the PackML standard? Production Maintenance Manual Automatic !!!!!

Answer 59

QUESTION 83 Which PackTags structures are defined in PackML? Command, Status, Admin !!!!! Status, Parameter, Configuration Command, Alarm, State Input, Output, In/Out

Answer 60

QUESTION 84 The batch produced on the machine has been finalized. Which state would be the correct state to go to afterwards? Finalising / Finalized Stopping / Stopped Completing / Complete -!!! MEN KUN HVIS MASKINEN KØRER BATCH KONTROL? Finishing / Finished

Answer 61

QUESTION 85 What is the lowest module in the ISA88.00.01 Physical Model? Equipment module - anden nederst. Mekatroniske moduler. (PackML video 55:00) Control module - Nederst. Mere simple funktioner på maskinen. !!!! Sensor - er ikke med I modellen Input / Output - er ikke med I modellen

Answer 62

QUESTION 86 What is the unit of the MachSpeed PackTag? Meters / Second Primary Packages / Minute !!!!!! Meter / Hour OEE - Overal equipment effectiveness = Availability * performance * quality

Answer 63

QUESTION 87 In which state is the machine producing its products? Execute !!!! Produce Running Fabricate