CilettiMixedPracticeTest2

Name:

Multiple Choice
Identify the choice that best completes the statement or answers the question.

a.	See Above	d.	See Above
b.	See Above	e.	See Above
c.	See Above

Multiple Response
Identify one or more choices that best complete the statement or answer the question.

Task No.:		Point(s):	2	Two answers are correct.	Cat. No.
An additional load is connected across an existing electrical parallel circuit. Which of the following statements are correct?
A	The current delivered by the power supply decreases. The total parallel resistance of the electrical circuit remains the same. The total parallel resistance of the electrical circuit increases by the value of the added resistor. The total parallel resistance of the electrical circuit decreases. The total power increases.
B
C
D
E

Task No.:		Point(s):	1	One answer is correct.	Cat. No.
Which of the following statements about testing solenoid coils is correct?
A	When a solenoid coil is checked, a reading of infinity on the ohmmeter indicates a partial short. An ohmmeter check of a good solenoid coil will indicate the value of the inductance. If there is an open circuit, an ohmmeter will indicate infinite resistance. If the solenoid coil is good, the ohmmeter will show infinite resistance. If all windings are completely shorted, the solenoid coil will have infinite resistance.
B
C
D
E

Task No.:		Point(s):	2	One answer is correct.	Cat. No.
Based on the control settings, find the peak-to-peak amplitude and the period of the waveform displayed on the scope screen, as shown below. How high is the frequency?
A	Vpp = 0.3 V, T = 100 ìs, f = 10 kHz Vpp = 1.2 V, T = 0.5 ms, f = 2 kHz Vpp = 1.5 V, T = 1 ms, f = 1 kHz Vpp = 1.6 V, T = 1.0 ms, f = 2 kHz Vpp = 1.8 V, T = 500 ìs, f = 2 kHz
B
C
D
E

Task No.:		Point(s):	2	One answer is correct.	Cat. No.
By observing the meters in the electrical circuit shown below, determine the type of failure in the circuit and which component failed.
A	R1 is shorted. R2 is shorted. R3 is shorted. R4 and R5 are open. R1 and R2 are shorted.
B
C
D
E

Task No.:

Point(s):

Two answers are correct.

Cat. No.

Gears are transferred on a conveyor belt and pass under a series of three proximity sensors to identify the material composition, as shown below. Each material type activates these sensors in a pre-determined combination, according the table shown below. The sorting assembly cannot distinguish between steel and aluminum. What can be the cause of this malfunction?

Sensor B1 is not adjusted properly.

Sensor B2 is not adjusted properly.

Sensor B1 is damaged and must be replaced.

Sensor B2 is damaged and must be replaced.

Sensor B3 is damaged and must be replaced.

Plastic

Brass

Steel

Aluminum

Sensor
B1

Low

High

Low

Sensor
B2

Low

High

Sensor
B3

Low

High

Task No.:		Point(s):	2	Two answers are correct.	Cat. No.
Which of the following statements about the functionality of the emergency lighting circuit, as shown below, are correct?
A	In the event of main power failure, the emergency lamp is not lighted. The lamp will be disconnected from the battery as long as the relay remains de-energized. As long as the main power is available, it energizes the relay coil. Since the relay coil is energized, the N.C. contact is open and the emergency lamp is not lighted. In the event of main power failure, the secondary of the transformer keeps the battery charged through the rectifier.
B
C
D
E

Task No.:		Point(s):	2	Two answers are correct.	Cat. No.
Which statements about the mode of operation of a reflective light barrier shown below are correct?
A	The interruption of the light beam by an object causes the output of the sensor to switch. Failure of the transmitter is evaluated as “no object present”. Failure of the transmitter is evaluated as “object present”. One advantage is that transparent and reflecting objects can be detected. If no object is present, the reflector must absorb the light emission.
B
C
D
E

Task No.:		Point(s):	2	Two answers are correct.	Cat. No.
If an object were caught in the upward movement of the car window, stalling the motor, what effect would this have on the window control circuit for a car door shown below?
A	Decrease in VR Decrease in IMOTOR Increase in IMOTOR Increase in VR Decrease in Analog Output Voltage
B
C
D
E

10.

Task. No.:		Points:	1	One answer is correct.

The force of retraction F (in N) of a double-acting cylinder when retracting should be calculated.
In which of the following formulas is the relationship correct mathematically described?

A
B
C
D
E

11.

Task. No.:		Points:	1	One answer is correct.

As shown below, the force required to advance the cylinder should be 600 N.
During the cylinder extension, the back pressure of the adjustable one-way flow control valve
is 1.5 bar. What is the applied air pressure pe in bar?

A		pe = 3.0 bar
B		pe = 5.5 bar
C		pe = 6.0 bar
D		pe = 6.5 bar
E		pe = 12.0 bar

12.

Task. No.:		Points:	1	One answer is correct.

Given for the system shown below: A1 = 50 cm2, A2 = 800 cm2, s1 = 16 cm. Determine s2.

A		s2=25mm
B		s2=0.256cm
C		s2=1cm
D		s2=2.56cm
E		s2=10cm

13.

Task. No.:		Points:	1	Two answers are correct.

Which statements about the component shown below are correct?

A		The air pressure at X acts on a cylinder surface. If the force exerted exceeds the spring force of the return spring, the piston moves and operates the contact set.
B		An electronic pressure sensor with digital output signal is shown. Instead of actuating mechanical contacts, the output is switched electronically.
C		Y is a knob for adjusting the spring force of the return spring.
D		When the piston moves to operate the contact set the connection between 2 and 4 is closed.
E		Y is a pushbutton to check the functionality of the pressure switch.

14.

Task. No.:		Points:	1	One answer is correct.

Which statement about a single-acting cylinder is correct?

A		The retraction of the piston is usually achieved by a spring.
B		The piston speeds in extension and retraction can be set.
C		Both piston sides will alternately be pressurized with compressed air.
D		Work can be conducted during extension and retraction of the piston.
E		It has a larger air consumption than a double-acting cylinder.

15.

Task. No.:		Points:	1	One answer is correct.

Which statement about the mode of action of the symbolically represented flow control valve is correct?

A		The compressed air can flow unthrottled from 1 to 2.
B		The stream of air flow can be continuously adjusted.
C		The compressed air can flow unthrottled through the valve in two directions.
D		The valve stops the flow of the compressed air from 2 to 1.
E		The valve can throttle the stream of air from 1 to 2 and 2 to 1.

16.

Task. No.:		Points:	1	One answer is correct.

Which symbol represents a pilot controlled 5/2-way double solenoid valve?

A		Picture A
B		Picture B
C		Picture C
D		Picture D
E		Picture E

17.

Task. No.:		Points:	1	Two answers are correct.

Which of the following statements about the control system shown below are correct?

A		The directional control valve 1V1 has four ports, two switching positions and is electrically actuated.
B		1V3 is an adjustable non-return valve.
C		The flow rate to retract cylinder 2A is determined by the adjustable one-way flow control valve 2V2.
D		The force for advancing the cylinder 1A is higher than the force for retracting it.
E		The directional control valve 2V1 has two ports, two switching positions and is electrically actuated.

18.

Task. No.:		Points:	1	One answer is correct.

Which statement about the mode of operation of the 3/2 - way valve in the switching positions a and b
represented symbolically is correct?

A		A
B		B
C		C
D		D
E		E

	Switching position a	Switching position b
A	2 - 3 open, 1 closed	1 - 2 open, 3 closed
B	2 - 3 open, 1 open	1 - 2 closed, 3 closed
C	2 - 3 closed, 1 closed	1 - 2 open, 3 open
D	1 - 2 open, 3 closed	2 - 3 open, 1 closed
E	1 - 2 open, 3 open	2 - 3 open, 1 open

19.

Task. No.:		Points:	1	One answer is correct.

Which of the following displacement step diagrams show the operations of the
cylinder 1A and the valve 1V1 correctly in the pneumatic circuit diagram below?

A		Diagram A
B		Diagram B
C		Diagram C
D		Diagram D
E		Diagram E

20.

Task No.:	1	Point(s):	1	Only one answer is correct.	Cat. No.:

Which component has to be maintained most often in a small DC machine?

A		Armature
B		Brushes
C		Permanent Magnets
D		Bearings
E		Commutator

21.

Task No.:	3	Point(s):	1	Only one answer is correct	Cat. No.:

A pump is connected with a clutch to a series-wound DC machine. What happens with the machine if the clutch is suddenly opened during operation?

A		The speed could get very high and probably destroy the machine.
B		The machine gets very hot.
C		The speed breaks down to zero.
D		The motor’s voltage will directly increase.
E		Nothing; the machine will continue to run at the rated speed.

22.

Task No.:	5	Point(s):	1	Only one answer is correct	Cat. No.:

The switching frequency of a power electronic for a DC machine is set to 2 kHz. This could cause:

A		Torque ripples.
B		Annoying noise.
C		More losses than necessary.
D		High armature currents.
E		Nothing; 2 kHz is an appropriate switching frequency and often used in industries.

23.

Task No.:	7	Point(s):	1	Only one answer is correct	Cat. No.:

The speed of a synchronous machine is higher than written in the data sheet. What could be the reason?

A		The amplitude of the three-phase voltage is too high.
B		The frequency of the three-phase voltage is too high.
C		The load connected to the machine is too small.
D		The load connected to the machine is too high.
E		The excitation of the machine is too low.

24.

Task No.:	9	Point(s):	2	More than one answer may be correct	Cat. No.:

Which components are used for energy transport between different machine units of a system?

A		Timing Belts
B		Washers
C		Bearings
D		Screws
E		Power Screws

25.

Task No.:	11	Point(s):	1	Two answers are correct	Cat. No.:

Which of the following statements about the gear train shown in the picture below is not correct?

A		The module of both gears has to be the same.
B		The pictured gears are used to lower the noise in operation.
C		The gear train exerts thrust (axial) forces.
D		The rotation speed of the upper shaft is smaller than the speed of the lower shaft.
E		The torque of the upper shaft is smaller than the torque of the lower shaft.

26.

Task. No.:		Points:	1	One answer is correct.

The basic difference between a PLC and a relay control system is that:

A		different types of input devices are used.
B		different types of output devices are used.
C		different input and output voltage levels are used.
D		one uses analog signals and the other uses digital signals.
E		one uses relay control logic and the other uses programmed instructions.

27.

Task. No.:		Points:	1	One answer is correct.

The symbol shown below in the ladder diagram ...

A		... can be thought of as a contact that is normally closed.
B		... can be thought of as a contact that is normally open.
C		... represents a capacitor.
D		... is always a logic 0.
E		... is always a logic 1.

28.

Task. No.:		Points:	1	One answer is correct.

Determine the number of possible combinations of a six digit binary number.

A		6 combinations
B		16 combinations
C		32 combinations
D		64 combinations
E		128 combinations

29.

Task. No.:		Points:	1	One answer is correct.

The largest decimal number that can be represented with eleven binary bits is …

A		... 255.
B		... 511.
C		... 1023.
D		... 2047.
E		... 4095.

30.

Task. No.:		Points:	2	One answer is correct.

The conversion of the floating point binary number 1011 1101.0110 to decimal is ...

A		187.625
B		189.375
C		189.625
D		190.375
E		191.375

31.

Task. No.:		Points:	1	One answer is correct.

If a given memory unit consists of 2400 bytes the memory capacity would be rated:

A		2,400 bits
B		4,800 bits
C		9,600 bits
D		19,200 bits
E		38,400 bits

32.

Task. No.:		Points:	1	One answer is correct.

If you want to know when one or both matching bits in two different words are logic ’1’ you would use the ...

A		... AND instruction.
B		... OR instruction.
C		... NOT instruction.
D		... XOR instruction.
E		... NAND instruction.

33.

Task. No.:		Points:	1	One answer is correct.

The status bit of switches and pushbuttons connected to a PLC input module are stored in the …

A		… process image input file.
B		… process image output file.
C		… user program.
D		… in the ROM.
E		… none of the above.

34.

Task. No.:		Points:	1	One answer is correct.

The Boolean equation for the logic represented in the ladder diagram shown below can
be expressed as …

A		Y = (A) + (C) + (BC)
B		Y = (A) + (B) + (CD)
C		Y = (A) + (CD) + (BC)
D		Y = A(BCD)
E		Y = (AB) + (CD)

35.

Task. No.:		Points:	1	One answer is correct.

By which system does the CPU communicate with input and output modules located on
the same rack?

A		Interface modul – IM
B		RS – 232 Interface
C		Multiple Point Interface – MPI
D		PROFIBUS DP
E		Backplane Bus

36.

Task. No.:		Points:	1	One answer is correct.

The PLC program is uploaded from the programming device into the PLC.
Into which specific CPU-Memory of the PLC is the program loaded?

A		block stack
B		load memory
C		system memory
D		process - image input table
E		work memory

37.

Task. No.:		Points:	1	One answer is correct.

In programs that are written in ladder logic, all outputs are represented by ...

A		... contact symbols.
B		... coil symbols.
C		... schematic load device symbols.
D		... either a or b, depends on the output interface module.
E		... negative contact symbols when relays are connected to outputs.

38.

Task. No.:		Points:	1	One answer is correct.

The maximum number of networks allowed in an Step 7 program is ...

A		... one.
B		... 8.
C		... 256.
D		... 1024.
E		... limited only by the memory size.

39.

Task. No.:		Points:	1	One answer is correct.

In PLC operation, a scan is normally a sequential process of ...

A		... reading control logic, evaluating outputs, and updating inputs.
B		... writing control logic, evaluating outputs, and updating inputs.
C		... reading/writing the status of inputs and updating outputs.
D		... reading the status of inputs, evaluating control logic, and updating outputs.
E		... updating and evaluating inputs according to control logic and updating outputs.

40.

Task. No.:		Points:	1	One answer is correct.

Given below is the truth table of a 3-input logic gate. Which logic gate represents the
behavior between inputs and output according to the truth table?

A	NAND gate.
B	AND gate
C	NOR gate
D	OR gate
E	XOR gate
		Input A	Input B	Input C	Output Q
		0	0	0	1
		0	0	1	1
		0	1	0	1
		0	1	1	1
		1	0	0	1
		1	0	1	1
		1	1	0	1
		1	1	1	0

41.

Task. No.:		Points:	1	One answer is correct.

An 8-bit binary counter has to count balls going into a box from a conveyor belt. A sensor
detects the passing of a ball. If it has counted one hundred balls, the binary value of the
counter is …

A		... 0110 0010
B		... 0110 1000
C		... 0110 0100
D		... 0001 0100
E		... 0000 0100

42.

Task. Points: 1 Only one answer is correct.
Into which CPU-memory is the PLC-program downloaded from the programming device?

43.

Task. No.: Points: 1 Only one answer is correct.
When does the S7-300/400 CPU show a signal fault?

a.	In OB 1 is called FC5. FC5 was not downloaded into the load memory.	d.	The load memory of the CPU is full.
b.	The CPU was turned into stop-mode when the statements in the program are executed.	e.	In Function 2 is called FC1. FC2 was downloaded into the load memory.
c.	A loop was programmed in Function 11.

44.

Task. No.: Points: 1 Only one answer is correct.
In ladder logic programs, all outputs are represented by:

a.	contact symbols.	d.	either a or b, depends on the output interface module.
b.	coil symbol.	e.	negative contact symbols when relays are connected to outputs.
c.	schematic load device symbol.

45.

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60.