Question 1

How do electronic timers provide time delays?

Accepted Answer

Electronic timers use solid-state components to provide the time delay desired. Some of these timers use an RC time constant to obtain the time base and others use quartz clocks as the time base. RC time constants are inexpensive and have good repeat times. The quartz timers, however, are extremely accurate and can often be set for 0.1 second times. These timers are generally housed in a plastic case and are designed to be plugged into some type of socket. An electronic timer can be designed to be plugged into a standard eight-pin tube socket. The length of the time delay can be set by adjusting the control knob on top of the timer.

Question 2

Pressure switches are found throughout industry in applications where it is necessary to sense the pressure of pneumatic or hydraulic systems.

Accepted Answer

A) True 
 B)False  True

Question 3

The term ____ means that the output voltage will be proportional to the supply voltage.

Accepted Answer

A)  piezoresistive 
B)  flow-through 
C)  ratiometric 
D)  differential 
A)  piezoresistive 
B)  flow-through 
C)  ratiometric 
D)  differential C

Question 4

Pressure switches are the only pressure sensing devices that an electrician is likely to encounter on the job.

Accepted Answer

A) True 
 B)False

Question 5

Programmable controllers contain ____ electronic timers.

Accepted Answer

A)  internal 
B)  external 
C)  no 
D)  transformed 
A)  internal 
B)  external 
C)  no 
D)  transformed

Question 6

____________________ pressure is the difference in pressure between the cut-in or turn-on pressure and the cut-out or turn-off pressure.

Accepted Answer

The answer of ____________________ pressure is the difference in pressure...

Question 7

____ timers operate by restricting the flow of air through an orifice to a rubber bellows or diaphragm.

Accepted Answer

A)  Pneumatic 
B)  Clock 
C)  Motor-driven 
D)  Capacitor time limit 
A)  Pneumatic 
B)  Clock 
C)  Motor-driven 
D)  Capacitor time limit

Question 8

Why are pneumatic timers popular throughout industry?

Accepted Answer

Pneumatic timers are popular throughout

Question 9

A metal bellows-type switch can sense pressures up to ____ psi.

Accepted Answer

A)  20 
B)  200 
C)  2,000 
D)  20,000 
A)  20 
B)  200 
C)  2,000 
D)  20,000

Question 10

Describe piezoresistive sensors.

Accepted Answer

Piezoresistive sensors are very popular

Question 11

Connecting eleven-pin timers into a circuit is generally even simpler than connecting the coil to power.

Accepted Answer

A) True 
 B)False

Question 12

What is the advantage of having a sensor that produces a proportional output current instead of voltage?

Accepted Answer

Sensors that produce a proport

Question 13

The off-delay relay is often referred to as DOE, which stands for "Delay On Energize."

Accepted Answer

A) True 
 B)False

Question 14

When a process has a definite on and off operation, or a sequence of successive operations, a(n) ____________________ timer is generally used.

Accepted Answer

The answer of When a process has a definite on...

Question 15

____________________ timers use a small AC synchronous motor to provide the time measurement for the timer.

Accepted Answer

The answer of ____________________ timers use a small AC synchronous...

Exam 4: Timing Relays, Pressure Switches and Sensors

How do electronic timers provide time delays?

Pressure switches are found throughout industry in applications where it is necessary to sense the pressure of pneumatic or hydraulic systems.

The term ____ means that the output voltage will be proportional to the supply voltage.

Pressure switches are the only pressure sensing devices that an electrician is likely to encounter on the job.

Programmable controllers contain ____ electronic timers.

____________________ pressure is the difference in pressure between the cut-in or turn-on pressure and the cut-out or turn-off pressure.

____ timers operate by restricting the flow of air through an orifice to a rubber bellows or diaphragm.

Why are pneumatic timers popular throughout industry?

A metal bellows-type switch can sense pressures up to ____ psi.

Describe piezoresistive sensors.

Connecting eleven-pin timers into a circuit is generally even simpler than connecting the coil to power.

What is the advantage of having a sensor that produces a proportional output current instead of voltage?

The off-delay relay is often referred to as DOE, which stands for "Delay On Energize."

When a process has a definite on and off operation, or a sequence of successive operations, a(n) ____________________ timer is generally used.

____________________ timers use a small AC synchronous motor to provide the time measurement for the timer.

General Principles of Motor Control, Symbols and Schematic Diagrams

Manual Starters and Overload Relays

The Control Transformer, Relays, Contactors, and Motor Starters

Float Switches, Flow Switches and Sensors

Limit Switches and Phase Failure Relays

Temperature Sensing, Devices M Solenoid and Motor Operated Valves

Hall Effect Sensors and Proximity Detectors

Basic Control Circuits and Photodetectors

Schematics, Wiring Diagrams Circuit (1), Timed Starting for Three Motors Circuit (2)

Float Switch Control of a Pump and Pilot Lights Circuit (3), Developing a Wiring Diagram Circuit (1)

Developing a Wiring Diagram Circuit (2) and Developing a Wiring Diagram Circuit (3)

Installing Control Systems and Reading Large Schematic Diagrams

Multiple Push Button Stations and Hand-Off-Automatic Controls

Forward-Reverse Control, Jogging and Inching

Dc Motors and Sequence Control

Solid-State Dc Drives and Starting Methods for DC Motors

Stepping Motors, the Motor and Starting Methods

Autotransformer Starting , Resistor and Reactor Starting for Ac Motors

Wye-Delta Starting, Part Winding Starters

Braking , Consequent Pole Motors, Variable Voltage and Magnetic Clutches

Variable Frequency Control

Troubleshooting, Motor Installation and Developing Control Circuits

Digital Logic and the Bounceless Switch

Programmable Logic Controllers and Start-Stop Push Button Control

Programming a PLC and Analog Sensing for Programmable Controllers

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