Switches Electronics 1 CVHS Basic Elements of a

Switches Electronics 1 CVHS

Basic Elements of a Circuit • Three Essential Elements – Load – Complete Path – Power Source • Additional Elements – Control Device – Protective Device

Electricity Generation • Six Methods Used to Produce Electricity – Chemical – Magnetism – Heat – Friction – Light – Pressure

Basic Switch Function • To open and close a circuit –Open (no connection) –Closed (connection) • Control device –Does not consume power

Schematic Terms • Pole- what the switch armature is connected to • Throw- the closed position of the switch Pole Throw

Single Pole, Single Throw • SPST • 1 pole, 1 throw • Example- room lights

SPST Animation

Single Pole, Double Throw • SPDT • 1 pole • 2 throws, 2 closed positions

SPDT Animation

Double Pole, Single Throw • DPST • 2 poles

Double Pole, Single Throw • Not 2 throws because of mechanical connection • Both armatures make contact at same time- one closed position

DPST

DPST Animation

Double Pole, Double Throw • DPDT • 2 poles • 2 separate closed positions

DPDT Animation

Switch Styles Toggle Slide

Switch Styles Rocker Push On/Off

Other Switches • Momentary contact switches –Push button switches • Rotary switches

Momentary Contact • Push Button Normally Open • PBNO • Red in color

PBNO

Momentary Contact • Push Button Normally Closed • PBNC • Black in color

PBNC

Rotary Switches • Used for complex circuits • Can have multiple throws

Rotary Switch • Example- Stereo input selector

#1) 3 P 1 T

#2) 2 P 5 T

#3) 3 P 2 T

#4) 3 P 3 T

Review • • • What are three basic parts of a circuit? What else can a circuit include? What are the six sources of energy? What is the main function of a switch? What is the difference between a throw and a pole? • What other types of switches are available?