Relais 12v refers to a relay with a driving voltage of 12V. The relay uses weak current to control strong current. 12V is the coil supply voltage of the relay, which belongs to weak current. The output can be 220V, 100V and other strong electricity, of course it is AC, the general relay, the contact can not pass too high DC voltage, it will cause the circuit to short circuit.

Relais 12v is an electronic control device, which has a control system (also known as an input loop) and a controlled system (also known as an output loop). It is usually used in automatic control circuits. It actually uses a smaller current to control more A kind of "automatic switch" for high current. Therefore, it plays the role of automatic adjustment, safety protection, and conversion circuit in the circuit.
When the input quantity (such as voltage, current, temperature, etc.) reaches the specified value, the electrical appliance that makes the controlled output circuit turn on or off. It can be divided into two categories: electrical quantity (such as current, voltage, frequency, power, etc.) relays and non-electrical quantity (such as temperature, pressure, speed, etc.) relays. It has the advantages of fast action, stable work, long service life and small size. Widely used in power protection, automation, motion, remote control, measurement and communication devices.