The following schematic shows the Relay Wiring Circuit Diagram for controlling an Air Conditioner or other higher high-current device from a microcontroller. This circuit is necessary if you are using a relay with a coil that needs more power than the microcontroller can supply. The diode protects the circuit in case the polarity is reversed.

high current relay circuit diagram

Related Post

Car Audi Amplifier Circuits - RF Filtering by
STM TS555 Datasheet for Low Power Timer
LM4856 Integrated Audio Amplifier Circuit Diagram Datasheet and Application
Wheatstone Bridge Single Op Amp Circuit Diagram
2009 GMC Sierra 1500 Instrument Panel Fuse Block, Relay Location and Circuit Breaker