Electric wire harnessIt is divided into main harness and branch harness, which shall be classified according to the system configuration of electric vehicles. The main harness is divided into battery power supply system harness, power switch harness and control system main power supply harness; The branch harness is divided into lighting signal harness, control system signal harness, combination switch harness, etc. The harness of lighting signal system can be divided into front lamp, front turn signal lamp, rear lamp, rear turn signal lamp, brake lamp, license plate lamp harness, etc. The harness and harness as well as the harness and electronic components are generally connected by plastic connectors. Generally, manufacturers use different hole numbers of connectors to distinguish. The main circuit harness of the whole vehicle is mostly centered on the controller and extends to the front and rear of the vehicle respectively.
The wires in the electric vehicle harness have different cross-sectional areas, and the allowable current values of wires with different cross-sectional areas are different. Generally speaking, the output line of the battery, the trunk line of the harness, the main power supply line of the control system, the power lock, and the connection of the battery pack are more than 1.5mm? The above wires; Lighting signal system and combination switch are more than 0.5 mm? The above wires; Brake power off, stop switch, etc. are used more than 0.15 mm? The above wires. Reasonable wiring harness processing and design is an important guarantee for the quality of electric vehicle products. Under the social background of advocating the concept of environmental protection, electric vehicles are becoming more and more popular. The harness manufacturer should actively study the layout method of electric vehicle wiring harness to minimize electric vehicle wiring faults.

 

Features of electric vehicle harness:
1. Power wire and motor wire: These two parts are the core parts of the electric vehicle harness. Before Haozhi Electronics produced the power harness, the allowable current value was determined to be below 15a, including 15a, and the cross-sectional area of the copper wire was 1.5 mm2, while the current value of the motor wire was larger, reaching above 15a, below 22a, and the cross-sectional area of the copper wire was 2.0 mm2.
2. Control the locking wire of weak current. The current intensity of the harness here is not large, 1.0a-3.0a, so the sectional area of 0.5 mm2 is sufficient.
3. Light, horn and alarm harness. The electronic horn is a warning sound component set for safe driving. The horn used in electric vehicles is almost active. Similarly, after full research with customers, Haozhi Electronics gives the data of current intensity 1.0a-3.0a, so the cross-sectional area is 0.5 mm2.
4. Data communication harness. Here, the allowable current of the harness is the smallest, less than 0.5a, and the wire diameter is 0.24 square mm. Obviously, this combination is sufficient for signal transmission of various parts of the electric vehicle.
Generally speaking, if the wire diameter is higher than the above specified value, the resistance of the electric vehicle harness is too large, and the voltage on the harness will be large when the large current such as starting the vehicle passes through, which can reach more than 2v, causing the controller to enter the undervoltage protection prematurely. Let's take 36v as an example. When the sectional area of the harness is too small, its internal resistance increases, which is equivalent to a series resistance. When the battery voltage is 36v and there is more than 15a current passing through, according to Ohm's law, if the internal resistance of the harness exceeds 0.1 ohm, the upper voltage will reach about 2v, and the voltage supplied to the controller is only 34v; When the battery voltage drops to 33v, the voltage supplied to the controller is only 31v. The controller enters the undervoltage protection, but the battery is not fully discharged.