Programmable Logic Controllers

41. A(n) ___ is created to show the logical relationship between devices.

D. relay logic diagram

57. Which file holds the PLC ladder logic program?

D., main program file

1. The symbol shown in figure is a:

D. Normally open pushbutton held closed.

20. Light-emitting diodes (LEDs) and laser diodes are used in ___ sensors.

D. Optical

61. You must energize the ___ coil to close an XIC Latch/Unlatch contact.

A control relay

4. A normally closed switch moves away from the stationary contact upon pressing the button.

True

5. In a normally open high temp switch, when it is closed, the circuit sends a signal that the temp is reached maximum limit.

True

9. The main reason to connect a normally open switch pin to an LED light's positive terminal is to supply power when the button pressed.

True

38. Input devices can be represented ___ in a relay logic diagram.

D. Multiple times

45. The ___ scan rate is the time required to execute the PLC ladder diagram once.

B Operational

39. You can place as many ___ as desired in series or in parallel in one rung in a relay logic diagram.

A input devices

60. An Allen-Bradley SLC 500 series PLC has counter addresses from ___ to ___.

D. C5:0, C5:255

19. A(n) ___ relay is typically used in the control of low-power circuits or other relays.

D. Control

34. According to rule six , all the input and output devices must be placed___.

D. Horizontally

13. The ___ coil causes the relay's contacts to either close or open.

D. Magnetized or demagnetized

58. An Allen-Bradley SLC 500 series PLC has an integer words addressed from ___ to ___.

D. N7:0, N7:255

12. The selection of manual or automatic switch should be based on all of the following except:

D. None of the above

50. To latch or unlatch a contact, two ___ are used.

A.pushbuttons

56. XIO is an acronym for ___.

A. Examine if open

30. Ultrasonic sensors use sound waves with frequencies above ___ kHz in order to detect the distance to an object.

A. 16

15. A(n) ___ sensor detects an object through the change in the sensor's dielectric.

A. Capacitive

22. In general, a relay consists of a magnetic core and its associated coil, __, spring, armature, mounting, and terminals.

A. Contacts

62. The ___ section allows you to print address and symbols with their description, instruction comments, and symbol groups.

A. Data Base

7. When no power is going, the function of a spring in the normally open switch is to :

A. Disengage two conducting points.

59. The main ladder logic diagram is held in ___.

A. File 2 or LAD2

31. A(n) ___ sensor is basically a semiconductor device (transistor) that can be switched by magnetic fields.

A. Hall effect

47. PLC program execution, or program ___, flows from left to right on each rung, starting from the top rung and continuing to the bottom rung.

A. Program scan

43.The ___ dialog box is divided up into the sections labeled General, Data Files, Program Files, Special, Data Base, and Miscellaneous Layout Options.

A. Report Options

26. A(n) ___ simply turns a motor on and off.

A.Motor starter

40. There are __ rules accepted as standard in the control industry for creating relay logic diagrams.

B. nine

51. File number ___ and ___ are system files.

B. 0 or zero, 1 or one

21. The two main sections of motor starters are __ and overload protection.

B. Contactor

37. In the relay logic diagram, ___ must flow from left to right.

B. Current

46. A method of testing the PLc system without actually closing or opening input devices is to test the PLC in the ___ mode.

B. Forced condition

53. The ___ report displays the number of slots available on the PLC.

B. I/O Configuration

6. Following is the electrical sign of a ___ switch.

B. Normally closed switch

2. The symbol shown in figure is a:

B. Normally closed switch held open

54. In order to change the program, the PLC must be in ___ mode.

B. Offline

27. The normally ___ pushbutton and switches are always open-until they are forced to close.

B. Opened

36. The ___ logic diagram is used to program the programmable logic controller (PLC).

B. PLC ladder

29. A relay is a device that acts on the same basic principle as the __ switch.

B. Reed

25. A(n) ___ switch is used in factory environments as an emergency or contact switch when a worker is using both hands for assembling a product.

B. foot

8. The 6-pin push button stainless steel switch's backside has 2 pins in the middle they are:

C. Both normally closed and held closed

44. ___ are placed on the top of each rung and typically describe the major function of the following rungs.

C. Comments

49. XIC is an acronym for ___.

C. Examine if closed

16.A(n) ___ sensor detects the presence of nearby metallic objects by measuring changes in magnetic fields.

C. Inductive

28. In the solenoid, when voltage is applied, the current through the coil produces a ____.

C. Magnetic field

14. A(n) __ sensor uses visible, ultraviolet, infrared, or laser lights and requires both an emitter to generate the light beam and a detector.

C. Optical

55. The control registers for an Allen-Bradley SLC 500 series PLC are addressed from __ to ___.

C. R6:0, R6:255

35. According to rule four, output devices cannot be connected in ___.

C. Series

18. A(n) ___ is a control device that uses electromagnetism to convert electrical energy into mechanical motion.

C. Solenoid

52. An Allen-Bradley SLC 500 series PLC has timers addressed from ___ to ___.

C. T4:0, T4:255

42. You can place ___ output device per rung, so you cannot place any output devices in series.

C. only one

33. Rule two states that one (and only one) ___ is placed near the right corner of the rung.

C. output

23. ___ applications are useful where the motor is to reverse its direction of rotation.

D. Plugging

24. Slowly accelerating a motor from standstill to operating speed is referred to as___.

D. Soft start

48. Which data file hold the error messages.

D. Status (S2)

32. In the solenoid, when the coil is___, the plunger returns to its normal position because of the spring action.

D. de-energized

17. The ___ detects over current through the magnetization when the line current generates.

D. magnetic overload relay

10. The 6-pin push button stainless steel switch's backside has 2 pins in the middle, if they are normally closed.

False

11. There are huge differences between manual and automatic transfer switches. Manual uses push and pull relay logic, and the automatic uses plug and unplug methods.

False

3. A normally open contact disconnects two conducting points upon pressing the button.

False