Arduino KY-019 Relay Module is used to control AC circuits, the relay acts as a switch that responds to a signal received from the Arduino, it has an integrated LED that indicates if the signal is high or low. Commonly used in IoT projects to control lights and other electronic appliances.
Description
Specifications
The KY-019 consist of a 1MΩ resistor, a LED, a 1N4007 rectifier diode and a 5VDC relay capable of handling up to 250VAC and 10A.
On the DC side of the board there are 3 pins for signal, power and ground. On the AC side there are 3 contacts, NC (Normally Closed), Common and NO (Normally Open).