1. Appearance requirements

After processing, the surface of the harness should be smooth, the skin should be even, and there should be no air holes, cracks, indentation, concavity and convex, damage, speckles, dirt, etc

The crimping between the harness and the terminal is firm without looseness. If it is welded with the terminal, it shall be firmly welded without loose core

2. Technical Requirements

The insulation shall be tightly extruded on the conductor and shall be easy to peel without damaging the insulator, conductor or tin coating. The insulation surface shall be flat and uniform in color

The average value of insulation thickness shall not be less than the specified nominal value, and the thickness of the thinnest point shall not be less than 90% - 0.1mm of the nominal value

The insulated core shall be able to withstand the AC 50Hz spark test specified in GB3048.9-83 as an intermediate inspection

3. Color separation of insulated core

The color of insulated core shall be easy to identify and not easy to erase, which shall comply with the provisions of wire and cable marking methods. If necessary, other identification methods are allowed, but should be specified in the product standard. Preferred colors and color sequence are as follows:

a) Single core cable: no preferred color

b) Two core cable: no preferred color

c) Three core cable: green/yellow, light blue, brown; Or light blue, black, brown

d) Four core cable: green/yellow, light blue, black, brown; Or light blue, black, brown, black or brown

e) Five core cable: green/yellow, light blue, black, brown, black or brown; Or light blue, black, brown, black or brown, black or brown

f) The green/yellow double color is the color of the grounding wire core. When there is a green/yellow double color grounding wire in the insulated wire of the cable, other insulated wire cores are not allowed to use green or yellow

Wire harness processing

4. Jacket

The sheath shall be tightly extruded on the stranded insulated core or inner sheath, and shall be easy to peel without damaging the insulator or inner sheath. The sheath surface shall be flat and uniform in color. The average value of sheath thickness shall not be less than the specified nominal value, and the thickness of the thinnest point shall not be less than 85% (0.1mm) of the nominal value

5. Mechanical strength

The crimping part shall be able to withstand the mechanical stress that may occur during normal use. Whether it is qualified may be checked by the following tensile strength test

Apply the specified tension for 1min, and explosive force shall not be used when applying force. This tension can also be applied through the tensile testing machine. The moving speed of the head of the testing machine should be between 25 ㎜ (1.0 in)/min and 50 ㎜ (2.0 in)/min, and there should be no falling off or fracture

The wire shall undergo the combustion test. After the test, the flame on the surface of the sample shall extinguish itself. The distance between the scorched part and the lower edge of the upper fixture of the test device shall not be less than 50mm

The wire shall be able to withstand the specified AC 50Hz non immersion voltage test, and the insulated wire cores of two or more round sheathed wires shall withstand the specified AC 50Hz non immersion voltage test

6. Insulation resistance

The insulation resistance of the harness shall be tested on the insulated core after the specified voltage test

7. Dielectric strength of conductor

The voltage is applied successively between all other conductors connected together for each conductor pair, and then between all connected conductors and sheaths:

a) Weak current harness: 1500V AC voltage, lasting for 1min

b) Strong current harness: 2000V AC voltage, lasting for 1min

c) Jacket: 3750V AC voltage, lasting for 1min

When the above voltage is applied, there will be no flashover or flashover

8. Appearance quality of flat quick connect terminal on harness

a) The terminal surface shall have a good appearance without scratches, burrs, obvious deformation, poor electroplating, etc

b) There shall be no damage, looseness or falling off at the riveting joint

9. Flat quick connect ends are grouped according to the nominal width of the insert

Ends within the scope of this standard include the following groups:

- 2.8mm (0.110in) series

- 4.8mm (0.187in) series

- 6.3mm (0.250in) series

Note: As long as the specified size is not affected and the test requirements are met, the shape of each part of the end can be different from that shown in the standard drawing, for example, there can be corrugated inserts, folding inserts, etc

10. Crosscutting area

The preferred cross-sectional area of the conductor shall be 0.5mm2, 0.75mm2, 1.0mm2, 1.5mm2, 2.5mm2, 4.0mm2 and 6.0mm2, or the corresponding AWG wire gauge