Technology of Connectors
The rating and performance of connectors are generally classified into the following four categories.
Rated voltage, Rated current, Contact resistance, Insulation resistance, Dielectric strength etc.
2. Mechanical performance
Insertion and Removal force, Insertion and extraction durability, Vibration resistance, Impact resistance etc.
3. Environmental performance
Heat resistance, Cold resistance, Moisture resistance, Gas resistance, etc.
4. Mounting performance
Solderability, Solder heat resistance, etc.
Maximum current that can be continuously flowed without deterioration of electrical and mechanical characteristics.
Voltage that can be applied continuously without deterioration of electrical and mechanical characteristics.
The electrical resistance of the contact bonded under specified conditions.
Normally, resistance (total resistance) generated by adding conductor resistance to contact resistance is often referred to as contact resistance, and stability is more important than resistance value.
Resistance between insulated contacts.
Limit value where dielectric breakdown does not occur when voltage is applied between insulated metal parts for 1 minute.
1. Insertion force, Removal force (Drawing force)
The force required to fully insert or extract a pair of connectors without coupling or operating similar devices.
2. Insertion and Removal durability
The number of times of insertion and removal guaranteed. It is also called insertion and removal frequency. Normally, it is determined according to contact pressure and plating.
Omron considers that environmental resistance performance is important in terms of contact reliability of connectors, and the specifications of insertion and removal tolerance are determined by how many times insertion and removal are conducted until nickel base plating of poorer environmental resistance is exposed.
Reference: Basic thickness of gold plating and number of times of insertion and removal (In some models this may not apply)
0.15μm : 50 times
0.4μm : 200 times
0.76μm : 400 times
Nickel base plating starts to be exposed due to friction of a gold plating on the surface of the contact by insertion and removal. However, it is possible to insert and remove quite a lot more than the guaranteed number before a base material(primarily copper alloy) is exposed since nickel is harder than gold and excellent in abrasion resistance, and the plating thickness is also considerably thicker than gold. Therefore, if it is just inserted and withdrawn, the contact resistance is low and stable even when the nickel base plating is exposed, and in terms of the contact resistance value, it can be said that there is no problem when considering only contact resistance value.
However, when using the contact of this condition under an adverse environment, contact resistance increases and becomes unstable due to corrosion of nickel. In consideration of this, Omron determines the number of times of insertion and removal based on friction condition of gold plating, and we recommend exchanging for those exceeding that number.
Vibration resistance, shock resistance, various environmental performance, mounting performance are guaranteed by conducting various environmental tests in terms of the environmental condition and the influence of aged deterioration.
These items are generally set as a single item. The tests are not conducted under complex conditions or standards.
Connectors have specific performance requirements depending on the function and structure. There are various performance characteristics such as lock strength, electric wire tensile strength, etc.