JC Technology Relay

Relay Parts of a Relay Un-magnetised = de-energised Armature Pivot Soft Iron core Coil of wire Coil Contacts Switch Contacts Un-magnetised = de-energised

Relay Current through coil magnetises soft iron core Armature pivots- attracted to core Contacts close - switching on secondary circuit +V 0V SPST Relay Magnetised = Energised

Relay SPDT Relay Three switch contacts – act as SPDT switch De-energised Energised

Relay DPDT Relay Six switch contacts – act as DPDT switch De-energised

Relay Interface device – connects two circuits together Primary circuit – connected to coil Secondary circuit – connected to contacts Separate electrical circuits

Relay Connects circuits needing different voltages to work Low voltage controlling high voltage Or High voltage controlling low voltage

Relay Sensor circuits used as primary circuit Fan motor turned on when its hot Automatic control

Relay DPDT Relay Automatic control of motor – curtains opening

Relay Relay Alarm Circuit Burglar opens door alarm sounds Problem: burglar closes door alarm goes off !!!!

Relay Latched Relay Alarm Circuit Alarm stays on when door is closed

Relay Reset the alarm PTB de-energises the relay