Programmable Logic Controllers - Chapter 4 Quiz

What are pushbuttons and switches also called?

• Analog input devices

• Digital input devices

• Digital output devices

• Analog output devices

What type of switch is always open until it is forced to close?

• Normally Open (NO)

• Normally Closed (NC)

• Single-break

• Double-break

What is the purpose of using indicators in a PLC system?

• To control motor speed

• To visually inspect operation of output devices

• To detect temperature changes

• To measure flow rate of liquids and gases

What type of sensor can detect the existence of an object without the need to touch it?

• Capacitive sensor

• Inductive sensor

• Proximity sensor

• Optical sensor

Which type of sensor uses a coil to generate a magnetic field to detect nearby metallic objects?

• Hall effect sensor

• Optical sensor

• Inductive sensor

• Capacitive sensor

What type of sensor uses sound above the normal human hearing threshold to detect distance to an object?

• Electrostatic ultrasonic sensor

• Magnetic flow meter

• Piezoelectric ultrasonic sensor

• Coriolis mass flow meter

What type of sensor uses visible, ultraviolet, infrared, or laser lights to detect objects?

• Optical sensor

• Hall effect sensor

• Capacitive sensor

• Proximity sensor

What type of device is used to measure both range and direction of an object based on known distances and angles in a triangle?

• Relay

• Triangulation system

• Flow meter

• Temperature sensor

What type of device is used to control the switching of a large amount of power using a relatively small amount of electrical power?

• Contactor

• Solenoid

• Solid-state relay

• Relay

What is the purpose of a motor starter?

• To control velocity, acceleration, and deceleration of a motor

• To measure flow rate of liquids and gases

• To protect the motor from low voltage and high temperature

• To turn a motor on and off