The basic properties of connectors can be divided into three major categories: mechanical properties, electrical properties and environmental properties.
1. mechanical properties
In terms of connection function, insertion force is an important mechanical property. Insertion force is divided into insertion force and pull out force (pull out force is also called separation force), the requirements of the two are different.
Maximum insertion force and minimum separation force are specified in the relevant standards, which indicate that the insertion force should be small from the point of view of use (hence the structure of low insertion force LIF and non-insertion force ZIF), while the separation force if too small will affect the reliability of contact. The insertion and removal force and mechanical life of the connector are related to the structure of the contact part (positive pressure), the coating quality of the contact part (sliding friction coefficient) and the size accuracy of the contact part (alignment).
2. electrical properties
The main electrical properties of connectors include contact resistance, insulation resistance and electrical strength.
① High quality electrical connectors should have low and stable contact resistance. The contact resistance of the connector varies from a few milliohm to tens of milliohm.
② Insulation resistance A measure of the insulation between contacts of electrical connectors and between contacts and enclosures, ranging from hundreds of megohm to thousands of megohm.
③ Electrical strength, or voltage resistance, medium voltage resistance, is a characterization of the connector contacts between or between the contact and the housing withstand rated test voltage ability.
3．Environmental performance Common environmental performance includes temperature resistance, humidity resistance, salt spray resistance, etc
❶ At present, the highest working temperature of the connector is 200℃ (except for a few high-temperature special connectors), and the lowest temperature is -65℃. When the connector is working, the current generates heat at the contact point, resulting in a temperature rise. Therefore, it is generally considered that the operating temperature is equal to the sum of the ambient temperature and the temperature rise of the contact point.
❷ The intrusion of moisture resistance will affect the insulation performance of the connection H and rust the metal parts. Constant humidity and heat test conditions are relative humidity 90%~95% (according to product specifications, up to 98%), temperature+40±20℃, the test time according to product regulations, at least 96 hours. Alternating wet – heat tests are more rigorous.
❸ When the salt spray resistant connector works in an environment containing moisture and salt, its metal structure and contact surface treatment layer may produce electrochemical corrosion, affecting the physical and electrical properties of the connector. To evaluate the ability of electrical connectors to withstand this environment, a salt spray test is prescribed. It is the connector hanging in the temperature controlled test box, with a specified concentration of sodium chloride solution with compressed air ejected, the formation of salt fog atmosphere, its exposure time by the product specification, at least 48 hours.
The above is the basic performance of connectors, Zhejiang Lianhe electronics Co., Ltd. specializing in the production of connectors, terminals, wire harness and other products, welcome new and old customers to come to buy.