The basic performance of the connector

The basic performance of the connector

The basic performance of the connector can be divided into three categories: Mechanical , Electrical and Environmental performance.

1.Mechanical performance:

• Mechanical performance including resistance to vibration and shock, locking mode, mechanical life, positioning key, Insertion force and withdrawal force, etc.
  Resistant to vibration and shock are important mechanical properties, such as aviation and aerospace, rail and road transport is particularly important in a particular application environment. Especially with the increase in aircraft or missile speed increased vibration and shock, can lead to isolation mounting plate cracks, wire and contact connections broken, and even lead to mating parts separated, especially in the resonance is more intense, the connector failure . Impact test shall be provided that the peak acceleration, duration and impact pulse shape, and electrical discontinuity of time.
• Locking is safe and reliable connections to prevent vibration caused by the separation of the connector and use, such as when you add security Insurance line threaded connection. Mechanical life is another important mechanical properties. Mechanical life is actually a durability index, the national standard GB5095 put it called mechanical operation. It is the first time you insert and pull out of a loop to the post required plug connector can normally complete its connectivity features (such as contact resistance value) as the basis for evaluation, targeting key is to prevent wrong mating connector the choice of bond structure.
• Insertion force and withdrawal force (pull force known as separation force), the two requirements are different. Insertion force maximum and minimum predetermined separation force, which indicates that, from the point of view of the use, the insertion force is smaller in the relevant standards, and, if the separation force is too small, it will affect the reliability of the contact. The insertion force connector and mechanical life contact structure (positive pressure size) contacting the coating quality parts (sliding friction coefficient) and the dimensional accuracy of contact arrangement (aligned degrees) related.

2.Electrical performance:

Electrical performance including contact resistance, insulation resistance, current and dielectric strength.
Contact resistance: high quality electrical connector should have a low and stable contact resistance. Connector contact resistance from a few cents to tens milliohms range.

• Insulation resistance: insulation performance indicators to measure the electrical connector between contact and contact with the housing, on the order of several hundred to several thousand megohms megohms range.
• Dielectric strength or said withstand voltage: the ability to withstand characterization connector between contacts or contacts with the housing rated test voltage, depending on the gap between the circuits (ie close contact spacing creepage distance) and connectors as the insulating material used.
• Current: wire in electrical connector and termination of the restriction.

Other electrical properties as well as EMI leakage attenuation of electromagnetic interference shielding effectiveness evaluation connector, generally in the frequency range of 100MHz ~ 10GHz test.

RF coaxial connectors, as well as the characteristic impedance, insertion loss, reflection coefficient, voltage standing wave ratio (VSWR) and other electrical indicators.

Due to the development of digital technology, in order to connect and transmit high-speed digital pulse signal, the emergence of a new type of connector that is high-speed signal connectors, accordingly, the electrical properties, in addition to the characteristic impedance, but also the emergence of new electrical specifications such as crosstalk (crosstalk), propagation delay (delay), delay (skew) and the like.

3.Environmental performance:

Common environmental performance including temperature, humidity, salt spray corrosion

• Temperature. Currently connector maximum operating temperature of 200ºC minimum temperature of -65ºC. Since the connector is working, current generates heat at the contact points, leading to temperature rise, it is generally considered to be equal to the ambient temperature and the temperature of the junction and. In some specifications, clearly defined maximum temperature rise connector rated operating current permissible.
• Moisture. Intrusion of moisture will affect the connector insulation and corrosion of metal parts. Damp heat test conditions for the relative humidity at 90% to 95% (depending on product specifications, up to 98%), the temperature is + 40 ± 20ºC, according to the specified test time minimum of 96h. Damp heat test is more stringent.
• Resistant to salt spray. When the connector works in an environment containing moisture and salinity, and its metal structure, the contact surface treatment layer may produce galvanic corrosion, affecting the physical and electrical properties of the connector. In order to evaluate the tolerance of the electrical connector such an environment, the salt spray test prescribed. It is the connector hanging in a temperature-controlled test chamber, with compressed air spray with a predetermined concentration of sodium chloride solution to form a salt spray atmosphere, the exposure time defined by product specification, at least 48h.
• Resistant to vibration and shock. Resistant to vibration and shock are important properties of electrical connectors, such as aviation and aerospace, rail and road transport is particularly important in a particular application environment, it is an important indicator of robustness and electrical test electrical connector contact reliability of the mechanical structure . In the relevant test methods are clearly defined. Impact test shall be provided that the peak acceleration, duration and impulse waveform and electrical discontinuity of time.

Other environmental performance. According to requirements, and other environmental performance as well as tightness (air leakage, fluid pressure), the liquid impregnation of the electrical connector (anti-abuse capabilities for specific liquids) and low air pressure.