1. Environmental performance:
Common environmental properties include temperature resistance, moisture resistance, salt spray resistance, vibration and shock.
Temperature resistance: The current maximum temperature of the waterproof connector is 200 ° C (except for a few high temperature special waterproof connectors), the lowest temperature is -65 ° C. Since the current generates heat at the contact point when the waterproof connector is in operation, since the current generates heat at the contact point due to the operation of the waterproof connector, resulting in a temperature rise, it is generally considered that the operating temperature is equal to the sum of the ambient temperature and the junction temperature rise. In some specifications, the maximum temperature rise allowed for a waterproof connector at rated operating current is specified.
Salt spray resistance: When the waterproof connector works in an environment containing moisture and salt, the metal structural parts and the surface treatment layer of the contact part may cause galvanic corrosion, which affects the physical and electrical properties of the waterproof connector. In order to evaluate the ability of the electrically waterproof connector to withstand this environment, a salt spray test is specified. It hangs the waterproof connector in a temperature-controlled test chamber and sprays it with compressed air at a specified concentration of sodium chloride solution to form a salt spray atmosphere. The exposure time is specified by the product specification for at least 48 hours.
Waterproof head function
Vibration and shock: Vibration and shock resistance are important features of electrical waterproof connectors. They are especially important in special applications such as aerospace and aerospace, railway and road transport. They are used to verify the robustness and electricality of the mechanical structure of the waterproof connector. An important indicator of contact reliability. There are clear regulations in the relevant test methods. Peak acceleration, duration, and shock pulse waveforms, as well as the time of electrical continuity interruption, should be specified in the impact test. Intrusion of moisture-resistant moisture can affect the insulation properties of the joint and corrode metal parts. Constant damp heat test conditions are relative humidity of 90% to 95% (according to product specifications, up to 98%) temperature +40 ± 20 ° C, test time according to product regulations, at least 96 hours. The alternating heat and humidity test is more stringent.
2, mechanical properties:
In terms of the connection function, the insertion force is an important mechanical property. The insertion force is divided into the insertion force and the extraction force (the extraction force is also called the separation force), and the requirements of the two are different. The insertion force is small (thus having a low insertion force LIF and a structure without ZIF insertion), and if the separation force is too small, the reliability of the contact is affected. Another important mechanical property is the mechanical life of the waterproof connector. Mechanical life is actually an indicator of durability, which is called mechanical operation in GB5095. It is a cycle of one insertion and one extraction to determine whether the waterproof connector can normally complete its connection function (such as contact resistance value) after the specified insertion and removal cycle.
Waterproof head function
The insertion force and mechanical life of the waterproof connector are related to the plating quality (sliding friction coefficient) of the contact structure (positive pressure) contact portion and the dimensional accuracy (alignment) of the contact arrangement.
3. Electrical performance
The main electrical properties of the waterproof connector include contact resistance, insulation resistance and electrical strength.
1 Insulation resistance is an indicator of the insulation performance between the contacts of the waterproof connector and between the contact and the casing, and is in the order of hundreds of megaohms to several gigaohms.
2 Resistance to electric strength, or withstand voltage, dielectric withstand voltage, is the ability to characterize the rated test voltage between the contacts of the waterproof connector or between the contact and the casing.
3 Contact resistance High quality waterproof connectors should have low and stable contact resistance. The contact resistance of the waterproof connector ranges from a few milliohms to tens of milliohms.