Common environmental properties include temperature, humidity, salt spray, vibration and shock.
① Temperature resistance At present, the maximum working temperature of rectangular connectors is 140°C (except for a few high-temperature special connectors), and the minimum temperature is -45°C. Since the current generates heat at the contact point when the connector is working, resulting in a temperature rise, it is generally believed that the operating temperature should be equal to the sum of the ambient temperature and the temperature rise of the contact point. In some specifications, the maximum temperature rise allowed by the connector at the rated operating current is clearly specified.
②The intrusion of moisture resistance will affect the insulation performance of the connection and corrode metal parts. The constant damp heat test conditions are relative humidity 90%~95% (according to product specifications, up to 98%), temperature +40±20℃, and the test time is at least 96 hours according to product regulations. The alternating damp heat test is more severe.
③ When the salt spray-resistant connector works in an environment containing moisture and salt, its metal structural parts and the surface treatment layer of the contact parts may cause galvanic corrosion, which affects the physical and electrical properties of the connector. To evaluate the ability of electrical connectors to withstand this environment, the salt spray test is specified. It is to hang the connector in a temperature-controlled test box, and spray the sodium chloride solution with the specified concentration with compressed air to form a salt fog atmosphere. The exposure time is specified by the product specification, at least 48 hours.
④ Vibration and shock Vibration and shock resistance are important properties of electrical connectors, especially important in special application environments such as aviation and aerospace, railway and road transportation. important indicator of sexuality. There are clear provisions in the relevant test methods. The shock test shall specify the peak acceleration, duration and shock pulse shape, as well as the time of interruption of electrical continuity.
⑤ Other environmental properties According to the requirements of use, other environmental properties of electrical connectors include sealing (air leakage, liquid pressure), liquid immersion (the ability to resist deterioration of specific liquids), low air pressure, etc.