Contact Details：

Insulation resistance refers to the resistance value exhibited by applying a voltage to the insulating part of the connector, so that leakage current occurs in or on the surface of the insulating part. It is mainly affected by factors such as insulating material, temperature, humidity, contamination and so on. The insulation resistance value provided on the connector sample is generally the index value under standard atmospheric conditions. Under some environmental conditions, the insulation resistance value will drop to an unnecessary degree.

1. Safety parameters

Insulation resistance refers to the resistance value exhibited by applying a voltage to the insulating part of the connector, so that leakage current occurs in or on the surface of the insulating part. It is mainly affected by factors such as insulating material, temperature, humidity, contamination and so on. The insulation resistance value provided on the connector sample is generally the index value under standard atmospheric conditions. Under some environmental conditions, the insulation resistance value will drop to an unnecessary degree. In addition, pay attention to the test voltage value of the insulation resistance. According to the insulation resistance (MΩ) = applied to the insulator voltage (V) / leakage current (μA) to apply different voltages, there are different results. In the test of the connector, the applied voltage generally has three grades: 10V, 100V, and 500V.

2. Pressure resistance

The withstand voltage is the critical voltage that can withstand higher than the rated voltage within a specified period of time between the mutually insulating parts of the contact pair or between the insulating part and the ground without causing breakdown. It is mainly affected by contact pair spacing and creepage distance and geometry, insulator material as well as ambient temperature and humidity, atmospheric pressure.

3. Combustibility

Any connector is inseparable from the current when working, which has the risk of fire. Therefore, the connector is required not only to prevent ignition, but also to self-extinguish within a short period of time once ignition and fire occur. When selecting, pay attention to choosing electrical connectors that use flame-retardant, self-extinguishing insulating materials.

4. Mechanical parameters

Single foot separation force and total separation force

The contact pressure in the connector is an important indicator, which directly affects the size of the contact resistance and the amount of wear of the contact pair. In most structures, it is quite difficult to directly measure the contact pressure. Therefore, the contact pressure is often measured indirectly by the separation force of one foot. For a circular pinhole contact pair, a standard pin with a specified weight is usually used to test the ability of the female contact to hold the weight. Generally, the diameter of the standard pin is -5μm, the lower limit of the diameter of the male contact. The total separation force is generally twice the sum of the upper and lower lines of the single foot separation force. When the total separation force exceeds 50N, it is quite difficult to insert and pull out manually. Of course, for some test equipment or occasions with special requirements, zero insertion force connectors, automatic detachment connectors, etc. can be selected.

5. Environmental parameters

The environmental parameters mainly include ambient temperature, humidity, rapid temperature change, atmospheric pressure and corrosive environment. The environment in which the connector is used, stored, and transported has a significant impact on its performance, so the corresponding connector must be selected according to the actual environmental conditions.

6. Ambient temperature

The metal material and insulating material of the connector determine the working ambient temperature of the connector. High temperature will damage the edge material, causing the insulation resistance and withstand voltage performance to decrease; for metals, high temperature can make the contact pair lose elasticity, accelerate oxidation and cause coating deterioration. The usual ambient temperature is -55~100°C, which may be higher in special occasions.

7. Wet

Relative humidity greater than 80% is the main cause of electrical breakdown. Humid environment causes the absorption and diffusion of water vapor on the surface of the insulator, which is easy to reduce the insulation resistance to below MΩ level. Long-term exposure to high humidity environment will cause physical deformation, decomposition and escape of products, resulting in breathing effect and electrolysis and corrosion. and cracks. Especially for connectors outside the equipment, environmental conditions such as moisture, water infiltration and pollution are often considered. In this case, sealed connectors should be selected. For water-tight and dust-tight connectors, the enclosure protection level of GB4208 is generally used.

8. Rapid temperature change

The humidity abrupt change test is to simulate the actual use situation of using the connector equipment to change from a cold environment to a warm environment, or to simulate the rapid change of the ambient temperature of space vehicles and probes. Abrupt temperature changes may crack or delaminate the insulating material.

9. Atmospheric pressure

At high altitudes where the air is thin, the plastic emits gas and contaminates the contact pair, which increases the tendency of corona, reduces the voltage resistance, and causes the circuit to short-circuit. When the high altitude reaches a certain value, the plastic performance deteriorates. Therefore, when using unsealed connectors at high altitudes, they must be derated. The recommended voltage derating factor at low air pressure is shown in Table 2.

10. Corrosive environment

According to the different corrosive environment of the connector, choose the connector with the corresponding metal, plastic and plating structure, such as the connector used in the salt spray environment, if there is no anti-corrosion metal surface, the performance will deteriorate rapidly. In environments containing a considerable concentration of SO2, it is not appropriate to use silver-plated contact pairs of connectors. Mold is also a significant problem in hot flash areas.