A “9VDC/225 Ohm” Electro-Magnetic Relay was used in the prototype. Contact Capacity of the relay (resistive Load) is 10A 250VAC/10A 30VDC; Panic Alarm Interface Circuit Schematic. Panic Alarm Arduino ...

In this quick Arduino tutorial I will explain how you can control a relay using the Arduino Board, one 1K and one 10K resistors, 1 BC547 transistor, one. ... Arduino Control Relay Schematic.