Controls, Switches and Energy Transformation

CONTROL The function performed by a component that can open or close a circuit switches and pushbuttons are examples of controls

SWITCHES SINGLE POLE SWITCH OPENS/CLOSES 1 CONTACT AT A TIME DOUBLE POLE CAN OPEN/CLOSE TWO CONTACTS AT ONCE ELECTRONS FOLLOW 1 PATH IN SINGLE THROW SWITCH DOUBLE THROW ALLOWS ELECTRONS TO FOLLOW 1 OF 2 PATHS P470

SWITCHES A switch is deemed to be closed when a connection is made. If you have a closed switch you will then have a closed circuit. Open Closed

Switches SwitchNumber of contacts that are open Number of possible paths for electrons Diagram Single Pole Single Throw 11 Single – Pole Double – Throw 12 Double – Pole Single – Throw 21 Double – Pole Double – Throw 22

SWITCHES ROCKER SWITCH

TOGGLE SWITCH

PUSH BUTTON

MAGNETIC CONTACT

ENERGY TRANSFORMATION CHANGE OF ONE FORM OF ENERGY TO ANOTHER FORM OF ENERGY

EXAMPLES OF ELECTRICAL COMPONENTS USED TO TRANSFORM ELECTRICITY INCANDESCENT BULBS- NEW FORM- LUMINOUS ENERGY

HEATING ELEMENT- NEW FORM- THERMAL ENERGY

PIEZOELECTRIC CRYSTALS- NEW FORM – MECHANICAL OR SOUND ENERGY

ELECTROMAGNETS – NEW FORM OF ENERGY – MAGNETIC ENERGY

RELAYS ( AST ONLY ) A RELAY OPENS OR CLOSES A CIRCUIT USING AN ELECTRICAL SIGNAL FROM ANOTHER CIRCUIT (THINK RELAY RACE-PASSING ON)

RELAYS ( AST ONLY ) COMMONLY USED TO CONTROL HIGH VOLTAGE CIRCUITS FROM A REMOTE DISTANCE, HEATING SYSTEMS, THE HORN IN YOUR CAR, AND MANY OTHER THINGS LIGHTING IN A THEATRE, HIGH VOLTAGE APPLIANCES (X-RAY MACHINE)