Chapter 2

1. Name three types of PLC modules.

   There are many types of modules such as:

   • A CPU module
   • A power supply
   • A analog input
   • A digital input
   • A chassis
   • A safety variant of any of these
2. What is the difference between a regular PLC module and a safety module?

   A safety module is designed to fail gracefully.

3. What is a stepper motor?

   A motor whose angle is controlled by pulses.

4. What is a servo motor?

   A closed loop motor.

5. How many pulses are required to move a stepper 180 degrees if the resolution is 1.8?

   100.

6. What is a motor encoder?

   A device that gives positional feedback.

7. What is a motor drive?

   A device that sends control signals to the motor.

8. What is the difference between an analog module and a digital module?

   An analog module will take in or send out a range of values. A digital module will only produce a full on or fully off condition.

9. What is a discrete module?

   A module whose input or output is either fully on or fully off.

10. What is a BOM?

    Bill Of Material...