Copyright (c) 2017 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. 1CHAPTER 1 Programmable Logic Controllers (PLCs): An Overview TEST 1 . 1 Choose the letter that best completes the statement. Answer 1. PLCs were originally designed as replacements for: 1. b
a) microcomputers. c) analog controllers. b) relay control panels. d) digital controllers. 2. Basically, the function of a PLC is to: 2. d
a) amplify various weak signal sources. b) control a high voltage output with a low voltage input. c) control the speed of motors. d) make logical decisions and control outputs based on them. 3. Modifying relay-type process control circuits usually involves 3. a
changing the: a) circuit wiring. b) input circuit modules. c) output circuit modules. d) circuit operating voltage levels. Copyright (c) 2017 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. 24. Which of the following is not an advantage that PLCs 4. c
offer over the conventional relay-type of control system? a) Smaller size c) Higher current capacity b) Less expensive d) More reliable 5. The main difference between a PLC and relay control system 5. d 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 hardwired relay control logic and the other uses programmed instructions. 6. The central processing unit: 6. a
a) looks at the inputs, makes the decisions based on the program, and sets the outputs. b) looks at the outputs, makes the decisions based on the program, and sets the inputs. c) serves only to store the program in memory. d) serves only to supply power to the backplane. Copyright (c) 2017 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. 37. PLC proprietary architecture 7. d
a) is the opposite to open architecture . b) makes it more difficult to connect to devices made by other PLC manufacturers. c) does not allow programs to be interchanged between different PLC manufacturers. d) all of these. 8. The output interface module connects to: 8. b
a) sensing devices such as switches or pushbuttons. b) load devices such as lamps or solenoids. c) a programming device such as a computer. d) all of the above. 9. Field or real-world devices refer to: 9.d
a) input devices only. b) output devices only. c) load devices only. d) all devices that are physically wired to the PLC. 10. The power required to operate the logic circuits 10 c
of the processor unit is typically: a) low voltage ac. c) low voltage dc. b) high voltage ac. d) high voltage dc. Copyright (c) 2017 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. 411. The control plan stored in the PLC is called: 11. a
a) a program. c) FORTRAN. b) a Boolean ladder. d) a microprocessor. 12. The programming device: 12. d
a) is used to enter the program into the memory of the processor. b) is commonly a personal computer. c) can be a hand-held device. d) all of the above. 13. The programming device must be connected to the controller: 13. d
a) at all times. c) when monitoring a program. b) when entering a program. d) both b and c. 14. The symbol in a ladder logic diagram: 14. a
a) can be thought of as a normally open contact. b) represents a capacitor. c) is always at logic 0. d) is always at logic 1. 15. The symbol in a ladder logic diagram 15. b
represents a: a) set of normally closed contacts. b) virtual relay coil. c) seal-in contact. d) field input sensing device.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller gradexam. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $30.49. You're not tied to anything after your purchase.
