The wiring harness is an important part of the articulation of various electrical and electronic devices, passing electrical signals between power supplies, switches, appliances and electronic devices, and is the primary carrier of electrical signal manipulation. Equivalent to the network body in the circuit, the production and manufacturing process to its potential failure forms and causes to be analyzed and studied, in order to control and improve product quality. We therefore have a corresponding reliability testing service to ensure that the wiring harness is factory qualified. In the wiring harness conduction test, we have the primary DC voltage drop as the key test requirements, according to national norms requirements and test specifications.
Ⅰthe wiring harness test process
1, plugged into the power supply and turn on the power switch.
2, first let the test machine initiative to start item-by-item testing, self-test through and then the sample into the corresponding test apparatus.
3, according to the requirements of the drawings to set the parameters of the product to be tested, the first use of bad samples test machine.
4、After the data is set, the product is tested and the test is completed, the test machine shows the test result, the test passes the PASS light, the machine announces "good" tone or voice prompt.
5, test results for bad, PALL light, the machine announced "unqualified" tone or voice prompts.
6、Good products are packed and placed neatly, put into the crate, and wait for the next process.
7, bad products into the bad products area, waiting for rework or destroyed.
Ⅱthe factors affecting the aging of the wire harness
Harness aging is a common problem of the harness, explore the causes of harness aging, prevention of harness supplies aging appears to be very necessary, resulting in the direct cause of aging harness is the insulation is lowered and struck through. Engineering machinery wiring harness factory to tell you, resulting in a number of factors to reduce insulation.
1, external force damage
Now a considerable number of wiring harness failure is caused by mechanical damage. For example: wiring harness installation wiring is not standardized construction, easy to cause mechanical damage; sometimes if the damage is not serious, it will take months or even years to lead to complete breakdown of the damaged parts to form a fault, sometimes serious damage may occur short-circuit fault, directly affecting the safety of production.
This situation is also very common, for example: the harness joint production is not qualified and in humid climatic conditions to do the joint, will make the joint into the water or mixed with water vapor, over time in the electric field under the action of the formation of water branches, gradually damage the insulation strength of the harness and cause failure.
Harness work in areas with acid and alkali, often causing the harness armor, lead skin or outer shield is corroded, the protective layer due to long-term exposure to chemical corrosion or electrolytic corrosion, resulting in the failure of the protective layer, insulation is reduced, will also lead to harness failure.
4、Long-term overload operation
Overload operation, due to the thermal effect of the current, the load current through the wiring harness is bound to lead to conductor heating, thereby increasing the temperature of the wiring harness. Long-term overload operation, the high temperature will accelerate the aging of the insulation, so that the insulation is pierced. Especially in the hot summer months, the temperature rise of the harness often leads to the first breakdown of the weak cable insulation, so in the summer months, the harness is particularly faulty. Such as the occurrence of auto spontaneous combustion accidents.
5、Wiring harness connector failure
The harness connector is a weak link in the line, caused by the direct fault of the personnel harness connector failure often occurs. In the process of making a harness connector, if the connector is not crimped tightly or heated sufficiently, it will lead to a reduction in the insulation of the harness head and thus cause an accident.
6、Environment and temperature
The external environment and heat source in which the harness is located can also cause high cable temperatures, insulation breakdown and even explosive fires.