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

LM4856 Integrated Audio Amplifier Circuit Diagram Datasheet and Application
Stereo Channel Selector by
An Introduction to Power Amplifier Classification (Class: A, B, C, D, E, F, G) - Circuit Diagram
High Current Adjustable Regulator Circuit Diagram Using LM117
TS472 Datasheet - Very Low Noise Microphone Preamplifier Applications and Circuit Diagram