What are wiring harnesses?
For easy installation and repair, the different specifications and colors of wires are combined by reasonable arrangement to make sure the electrical equipment can work under poor conditions, which consists of the insulating cover, terminals, wires, and insulating wrapping materials.
What’s the difference between cable assembly and wire harness?
"cable assembly" and "wire harness" are often used interchangeably, and both of them are used to transmit power and signals, but they still have some differences.
Wire harnesses usually consist of multiple wires inside the sleeve. The outer sleeve is made of thermoplastic or thermoset plastic which does not provide much protection against abrasion or temperature fluctuations. These harnesses are used in less harsh environments; for example, within machine housing units. Cable assemblies also have multiple wires covered by an outer jacket, but the jacket is made of a heavy-duty material that can work in a poor environment.
Cable assemblies combine multiple similar wires in a bundle and cover them with sleeves and jackets for additional protection. When use cable assemblies replace bundle wires, the number of cable wires is significantly reduced, which makes the assemblies look organized and tidy. Cable assemblies make the wires inside have a longer life because they are protected from vibration, abrasion, moisture, and other harsh conditions. And it becomes very easy to manage, repair, and replace such cables.
Customization Wiring Harnesses Process
Flexcontac treats each project with high enthusiasm and dedication, our goal is to meet customers’ requirements, to realize the design into actual products. Below is the general process of the customization wire harness:
Negotiate with customers about technical requirements.
Cost evaluation and quoting
When the price is confirmed, engineering drawings will be sent for approval.
Make prototypes, send pictures or actual wire harnesses for customer testing
After prototypes are approved, arrange mass production, reply OC(order confirmation) with lead time.
Packing and delivery.
Manufacturing Wire Harness Process in-House:
Incoming materials inspection
Test the environmental performance through the instruments according to ROHS standard, should not contain harmful materials such as lead and mercury.
Wire cutting: no scratching of the wire, flat cut, dimensions as required, each bundle marked with the length and its wire gauge
Stripping: Should not strip the conductor copper wires, cut and strip the opening smoothly, the size within the tolerance
Twisting: twist the wire in the joint place, not scratching the surface of the wire, must twist the copper wire tightly, not with the loose wire
Tin immersion: ensure the tin surface is flat, bright, and smooth, with no burr.
Sleeve Wearing: Pay attention to the direction of the sleeve. The terminal position meets the requirements
Crimped terminals: terminal crimping tension or height should meet the requirements, no deep crimp, shallow crimp, flying wire, terminal deformation, too high and too low, and other defectives
Assembly: assembled according to the requirements of the engineering drawings.
Test: Conductivity test, using the instrument for the conductivity test, do not appear broken, poor contact and insulation.
Inspection: 100% inspection, the appearance shall not have oil, sand, abrasion, cracks
Packing: pay attention to more and less packing and mixed packing, clear marking with shipping marks.
Wiring harness testing and inspection
Cable assembly and wire harness testing and inspection is the guarantee of product quality, the inspection results can reflect design technology, process work, operation level, production capability, and the whole enterprise management level.
Inspection includes the observation of raw materials, intermediate products, and finished products, conducting appropriate measurement or test, comparing the test result and the specific result, determining the batch product passed or not. The sequence is incoming inspection, process inspection, and final inspection.
The test and inspection are based on standards according to IPC-A-620 and UL486A. Here below is the form or inspection details:
Item | Content | Standard | Inspection tools |
Function testing | Conductivity | 1. Test both ends of a cable , should not open circuit (infinite resistance value) | |
2. Measure the two adjacent cables, should not be a momentary circuit (resistance value of zero) | |||
3. Test both ends of the corresponding cables, | |||
4. Wrong wiring method unacceptable (wire sequence) | |||
5. Unacceptable poor contact or non-functioning. | |||
Plugging test | The male and female connectors are plugged ,make sure they can be completely mating. | Practical operation | |
Terminal pull test | Crimped terminals pull force meets customer requirements | Tensiometer | |
Insulation resistance test | Use DC500V megohmmeter to test the insulation resistance of the cable harness. If the test resistance is less than 100M0 that is unacceptable. | Insulation resistance | |
Dielectric strength | Apply AC1500\7min or AC1800V/S between charged and uncharged, breakdown current W2mA. No breakdown | Hi-pot Tester | |
Apperance and dimension inspection | Wire jacket | 1.Wire jacket should not be any damaged, should be smooth surface, no grain | |
4 Crimp terminals should not any drop, breakage, damage, deformation and oxidation. | |||
Wire dimensions | Size meets customer requirements | ||
Hall cable harness | Electrical performance | Test with motor, handle and controller, press the hand controller up and down keys, whether the motor rotates in accordance with the specified direction | Motor, controller |
Joystick cable harness | Electrical performance | Test with the motor, controller, lifting column, press the hand controller up and down keys, whether lifting column is | Motor, controller |