How to Choose a Circular Connector?

Connector is also called as plug socket, it's widely used in all kinds of electrical circuits to connect or disconnect the circuit. The electrical connector has many types and wide applications, proper selection of circular connector is also an important way to improve the connector reliability.

Electrical parameter requirements

1. Rated voltage
   Rated voltage is also known as working voltage, it's mainly determined by the insulation materials used by circular connector and the distance between the contact pairs. Some component devices may not be able to perform their functions when using below the rated voltage.
2. Rated current
   Just the same as the rated voltage, the circular connector may not work normally in the current below the rated current. In the design of circular connectors requirements for rated current are met through the thermal design of the circular connector, because the contact pairs will be heated when current passed due to the existence of conductor resistance and contact resistance.

Security parameter

1. Withstand voltage
   Withstand voltage refers to the critical voltage between the insulated parts of the contact pairs or between the insulated part and the grounding, which is higher than the rated voltage in the prescribed time but does not produce the breakdown phenomenon. It's mainly affected by the distance between contact pairs, creepage distance and geometry, insulator material, ambient temperature and humidity, and atmospheric pressure.
2. Combustibility
   Any connector is inseparable from the current at work, so the danger of fire exists. Therefore, the connector is not only required to prevent ignition, but also required for self extinguishing in a short time when ignition and fire occur. When choosing a connector, please choose the circular connector with flame retardant and self extinguishing insulating material.

Mechanical parameters

1. Single foot separating force and total separating force
   Contact force is an important indicator in the connector, it directly affects the value of contact resistance and the wear amount of contact pairs. In most structures, it's quite difficult to measure the contact force directly, so the contact force is generally calculated through single foot separating force.
2. Mechanical life
   The mechanical life of the connector refers to the lifespan of the plug, which is generally defined to be 500～1000 times. When this regulated mechanical life is reached, the contact resistance, insulation resistance and withstand voltage of the connector should not exceed the specified value .

Environmental parameters

1. Temperature
   The metal material and insulation material of the connector determines the working temperature of the connector. High temperature will damage the insulation material and cause the decrease of insulation resistance and withstand voltage. As for metal materials, high temperature can make the contact pairs to lose elasticity, accelerate oxidation and deposit change.
2. Humidity
   Humid environment leads to the absorption and diffusion of water vapor on insulator surface, thus easily reducing the insulation resistance to below M Omega. Working in high humidity for long term, physical deformation occurs and resultant decomposes and emits, generating the respiration effect and electrolysis, corrosion and crack.
3. Corrosive environment
   According to different corrosive environments, choose the connectors with metal, plastic and plating structures. For example, when using in the salt-fog environment, the performance of connector deteriorates rapidly without the anti-corrosive metal surface. In hot flush areas, mold is also an important problem.