What is the function of a car relay?

Update:22-03-2023
What is the function of a car relay?

The basic function of the automotive relay is to use a small current to control the "automatic switch" that runs on a large current. It plays the role of automatic adjustment, safety protection, conversion circuit, switch and so on. If a car relay is bad, the simplest symptom is that some function of the car cannot be used. If the oil pump relay is damaged, the engine will not start. If the headlight relay is damaged, the headlights will not come on. If the starter relay is bad, the car won't start.

1. The function of the relay is to use the switch to control the relay coil, and then the working contact point of the relay is closed or broken. One end of the contact point is connected to the main line current, and the other end is connected to the electrical appliance to be controlled;

2. To achieve small current control large current, prevent large current from burning the switch, and protect the circuit and switch.

Just open the hood to find the relay mounting box, and you can find traces of the relay. Relays are used in lights, wipers, starters, air switches, electric seats, electric doors and windows, anti-lock brakes, suspension controls, audio, etc. There are two main aspects of relay control,

One is the control system,

The second is the controlled system. Controlling a large current with a small current is a characteristic of a control relay.

How to install the car relay: 1. Installation orientation: If the installation orientation is the same as the impact resistance orientation of the relay, the performance indicators of the relay can be fully utilized. It is recommended that the impact direction be perpendicular to the movement direction of the contact point and the armature, which can effectively improve the anti-vibration and anti-shock performance index of the normally closed contact in the non-excited state. When installed, the axial direction of the relay contacts is parallel to the road surface, which can prevent contact splashes and burnt substances from falling on the contact surface, and improve contact reliability. Multiple groups of relays should prevent the small load contacts from being under the heavy load contacts.

2. Closed installation: When several relays are installed together, it will cause abnormal combustion. The recommended distance is generally 2mm. Short distance installation of polarized or magnetic latching relays will directly affect the operating voltage.