The Relay for Horns

                                                    The Relay for Horns

When a single electric horn is used on the car body, it is generally controlled directly by the horn button. However, in order to get a better sound and a pleasant sound effect, most cars are often equipped with two kinds of speakers, high and low, or even electric speakers with three different tones of high, medium and low. When two or one electric speakers work at the same time, the current Up to 15A or more than 20A. If the horn button is used for direct control, the large current will quickly burn the horn button, so the horn relay is used.

The button controls the on and off of the current in the relay coil, and then controls the horn through the relay contact. The horn relays used in 12V electric vehicles generally require a closing voltage of not more than 6V and a release voltage of not less than 3V; the relay coil is usually 1000 turns, and the resistance at 20°C is 26Ω; the rated current of the relay is generally more than 20A. The rated current of the basin-shaped electric horn is usually 3A~4A. Although the current is not large, in order to improve the service life of the button, many cars are still equipped with a horn relay.

How the horn relay works

Press the horn button 3, the relay coil 2 is energized, the contact arm 1 and the contact 5 are engaged, and the power circuit of the horn is connected. Release the horn button 3, the relay coil 2 is de-energized, the contact 5 is separated from the contact arm 1, and the horn does not work.