The wire harness provides an overall set of service equipment for a certain load source group, such as trunk lines, switching devices, control systems, etc. The basic research content of traffic theory is to study the relationship among traffic volume, call loss and wire harness capacity, so wire harness is an important basic concept in traffic theory. This article mainly explains the definition, composition, material and selection of wire harness.
1. Definition of wire harness
Set up a communication bridge between two or more isolated and disconnected electronic circuits, so as to make current flow and realize various functions of various electronic components. It is an indispensable part of various electrical appliances and electronic equipment.
2. Composition of wire harness
Signal harness: injection molding is required.
Common wire harness components are: terminals, plastic parts, wire.
Complex wire harness components are added: tape, casing, labeling, tape, sheath, etc.
3. Materials of wire harness
Take automobile wiring harness’s requirements on materials as an example: its electrical performance, material dispersion, temperature resistance and so on are all higher than the general wiring harness requirements, because automobile wiring harness involves personal safety, so the requirements on material safety are more stringent. The following 6 points are the requirements for wire harness materials in automobile wire harness;
(1) Shield wire should be used for weak signal sensor.
(2) Automatic transmission wire is hydraulic oil resistance, high temperature resistance, good temperature stability wire.
(3) The wire of wiring harness on the roof of the luggage compartment should keep its elasticity at low temperature, so choose the cold-elastic wire to ensure its normal work.
(4) The ABS wire harness assembly uses stranded wires with a high temperature resistance of 150-200 °C, a hard and wear-resistant outer protective insulating layer, but with a core greater than 133.
(5) The wires used in the power line such as starter alternator output line, battery line are special wires that can withstand large currents, have good heat dissipation performance of the insulating layer, and reduce the voltage.
(6) The ambient temperature around the engine is high, and there are many corrosive gases and liquids. Therefore, high-temperature, oil-resistant, vibration and friction resistant wires must be used in the wiring harness of the engine.
4. Selection of wire harness materials
The quality of wire harness material directly affects the quality of wire harness, and the choice of wire harness material is related to the quality and service life of wire harness. So in the choice of wire harness products, must not covet cheap, cheap wire harness products may be inferior wire harness materials.
So how do you tell the difference? Please look at the following 4 points. Wire harness is generally composed of wire, insulation sheath, wiring terminal and wrapping material. As long as you know these materials, you can easily distinguish the quality of wire harness.
(1) Selection of wires material: select the corresponding wire material according to the different service environment.
(2) Selection of insulating sheath materials: common materials of sheath materials (plastic parts) include PA6, PA66, ABS, PBT, pp, etc. Flame retardant or reinforced materials can be added to plastics according to the actual situation to achieve the purpose of strengthening or flame retardant, such as adding glass fiber reinforcement.
(3) Selection of terminal materials: the copper used for terminal materials (copper parts) is mainly brass and bronze (the hardness of brass is slightly lower than that of bronze), among which brass accounts for a large proportion. Additional, can choose different plating layer according to different demand.
(4) Selection of wrapping materials: wire harness wrapping plays a role in abrasion resistance, flame retardant, corrosion resistance, interference prevention, noise reduction and appearance beautification. Generally, wrapping materials are selected according to the working environment and space size. There are usually tape, corrugated tube, PVC tube, etc.
Post time: Jul-28-2022