Method to choose connectors

Choosing connectors includes use environmental conditions, electrical, mechanical, terminal types, and etc. Reasonable selection is a precondition to guarantee normal work of connector, and right operation is a key to guarantee product function realization. We provide customers with high-grade products, at the same time, hope that customers choose and use our products properly.

Please contact with us if you have any special requirements.

1. Environmental conditions of operation

1.1. Environment temperature

　　Environment temperature should accord with the scope of the environment temperature in the catalogue. If the environment temperature is out of the range, the plated metals layer or insulator will be damaged. If the environment temperature is very low, the insulators will be cracked. So the bad environment temperature means bad performance and lost function. 

1.2. Damp or water

Damp or water will make insulator surface bring a layer of water membrane. It will make insulating function fall, even make that two close contacts is connected together. In a general way, the connector, which usually works in very damp environment or water, should be waterproof.

1.3. Low atmospheric pressure

Under high altitude circumstance, atmospheric pressure decreases except in isobarically seal storehouse. When the product is on low atmospheric pressure condition, dielectric-withstanding voltage will fall. If a delivered voltage is higher than the prescriptive technical datum, electric breakdown may take place to result failure.

1.4.Corrosive environment

It means the atmosphere around product, such as the atmosphere on the sea and in the chemical material storehouse, etc. These environments will make metallic part and insulator of connector decayed or corroded. While selecting connectors, customer should put forward special requirements in order that the product can meet own needs. Some insulator of connector isn’t resistive to banana water, benzene and acetone impregnant, etc, so pay attention to the specification in the catalogue.

1.5. Mechanical condition

It means vibration, shock, bump, acceleration mechanical effect, etc. A compatible connector is to be selected according to the catalogue. In actual usage, cable is to be fixed by cable clippers or other ways after cable end being linked to contact.

2. Terminal types

Terminal types mean connective types between cable and connector. There are lots of types. During selection, the usage environment, reliability requirement, and other existing conditions should be taken into consideration.

a) Crimp type, the type of better mechanical strength, fine electrical performance, high reliability. However the flexibility is poor, and only compatible to specified cables.

b) Solder type, the type of high flexibility, easy operation, etc.

3. Electrical performance

3.1 Contact resistance

Due to wastage during circuit transmission, especially, when amplitude is not big, signal voltage would drop obviously because of contact resistance. The signal decay is adverse to transmission. The connector adopting twist pin possesses very good contact reliability, as it is contacted by a number of points, and compatible to transmission of low voltage and puny current.

3.2 Rated voltage

Rated voltage, in electric connector, means the voltage, between mutual insulative parts. While operation voltage of connector is chronically more than rated voltage, its insulator performance will drop or the connector will become useless.

3.3 Rated current

The value of Rated current is confirmed during thermal design course of product. Over current can bring a mass of heat, and make insulator damage or plating layer of contact softened so that failure appears. Therefore, user cannot increase operation current. For higher reliability, smaller than rated value should be used according to contact number of connector.

3.4 Shielding properties

Because of high densities mounting and exterior electromagnetism radialization, generally, outer metallic shell is used to shield outward and inward electromagnetism radialization. Notice outer metallic shell should connect ground well.

3.5 Resistance match

　　Resistance match should be cared to coaxial connector used to transmit high or radio frequency signal. If resistance match is not selected accurately, signal will attenuate obviously.

4 Insulate and safety

4.1 Insulation resistance

Insulation resistance means the resistance brought in surface or inner as supplying voltage to insulator. If insulation resistance is small, drain current will be large and the transmitting current will escape to bring current loss, as supplying voltage to insulator. Insulation resistance is correlative with selected materials and operation environmental conditions.  Under high heat or damp etc. conditions, insulation resistance gets small. Please pay attention to those prescribes in the catalogue.

4.2 Dielectric withstanding voltage

Dielectric withstanding voltage means the instantaneous peak voltage withstanding between mutual insulating contacts and between contact and outer shell, brought by surge, instantaneous switch, hit, etc, and is correlative with insulator material, ambient temperature, humidity, atmosphere pressure, etc.

4.3 Combustibility

Combustibility means flame retardant and self-extinguishing ability of insulator except for glass and porcelain. It is important to space flight, some space occasion and household appliances.

4.4 We can supply product according with ROHS needs.

5. Mechanical performance

5.1 Mechanical life

Mechanical life means the cycle number, which plug and receptacle of connector can insert and pull out, generally is 500,1000 times. Please care that most products all cannot support hot inserting and pulling, in other words, cannot support insert or separate with voltage. If user needs it, a requirement should be put forward during order.

5.2 Interference of outline size

Interference of outline size mainly means that product outline size should accord with self-design assembly space, to consider whether product is interferential with other parts or component in size.

5.3 Locking method

For rectangle connector, there are bolt locking, quick ouch, quick inserting slice, and etc. locking method. For circular connector, there are thread locking, quick bayonet, quick steel ball locking method, etc. For usual thread and bolt locking method is only the same with the occasion, where inserting and pulling need not often do.

5.4 Locating system

Locating system mainly prevent that connector is inserted and joined incorrectly. If customer needs diversiform system, it will get by selecting diversiform codes for locating.

5.5 Assembly method

Assembly method includes fixing, floating and free end assembly.

6. Notices for use

6.1 　As most products don’t prevent oblique insert, please don’t insert them in crosswise direction as pull them out, and don’t pull them out by left and right sway method. Especially for the hermetical product which uses glass insulator as support, its solder end should not been pulled at will, even should not be swayed left and right.

6.2 　The miniature connector should be thrust in slowly after it is aimed by present.

6.3　As most products all cannot support hot inserting and pulling out, they should be inserted and pulled out after the circuit is cut off.

6.4　The product, which isn’t yet inserted to the end or isn’t locked up, cannot be supplied voltage. As an abnormal condition happens for inserting, please don’t insert it with a strong hand.

6.5　Before using a connector, please check if there is foreign matter. If contact need be cleaned, it should be used for silk dipped absolute ethyl alcohol. Certainly, cotton cloth should not be used to clean.

6.6 　Connector should save up in the environment, whose temperature is in the range of 5℃ to 35℃, relative humidity is more than 80%, and where is no corrosiveness gas. 

6.7　 For the product, whose terminal lead type is crimp type, its sectional area of core of conductor should accord with the prescribed limit in the catalogue.

6.8 　For the product, whose terminal lead type is solder type, it should use neutral soldering flux to keep from polluting insulator. Otherwise, the insulated characteristic of products may drop.

Orders

According to the catalogue, a connector is selected, please refer to the requirements of order goods mark for completing the procurement contract correctly.