Common environmental properties include resistance to temperature, humidity, salt spray, vibration, and impact.
1. Temperature resistance
Currently, the maximum working temperature of the connector is 200 ℃ (except for a few special temperature connectors), and the minimum temperature is - 65 ℃. Due to the temperature rise caused by the heat generated by the current at the contact during the operation of the connector, it is generally believed that the operating temperature should be equal to the sum of the ambient temperature and the contact temperature rise. In some specifications, the maximum allowable temperature rise of the connector under the rated operating current is explicitly specified.
2. Moisture resistance
The invasion of moisture can affect the insulation performance of connectors and corrode metal components. The constant damp heat test conditions are relative humidity of 90% to 95% RH (up to 98% RH according to product specifications), temperature of - 20~+40 ℃, and test time according to product regulations (≥ 96h). The alternating damp heat test is more rigorous.
3. Salt fog resistance
When a connector works in an environment containing moisture and salt, its metal structure and contact surface treatment layer may produce electrochemical corrosion, which will affect the physical and electrical properties of the connector. The salt spray test is used to evaluate the ability of the connector to withstand this environment. It is to hang the connector in a temperature controlled test box, spray the specified concentration of NaC1 solution with compressed air, and form a salt spray atmosphere. The exposure time is specified by the product (≥ 48h).
4. Resistance to vibration and impact
Resistance to vibration and shock is one of the important properties of connectors. In special application environments, such as aviation and aerospace, railway and highway transportation, resistance to vibration and impact is particularly important. It is an important indicator for testing the robustness of the mechanical structure and electrical contact reliability of connectors. The peak acceleration, duration, and shock pulse waveform, as well as the time of electrical continuity interruption, should be standardized during the impact test.
5. Other environmental performance
According to usage requirements, other environmental properties of the connector also include leakproofness (air leakage, liquid pressure), liquid immersion (ability to degrade specific liquids), low air pressure, and so on.
