The most important thing is the size of the contacts. So we should pay more attention to the selection. There are three other issues that need to be understood. Please understand them in detail.
Touch the switch first to see the shell material. The main switch brands in the market generally choose PC material, PC material is also called bullet-proof glue. The characteristics of impact resistance, high temperature resistance and non-discoloration are very important for the control of electrical switches.
First look at the contact point, that is, the contact point of conductive parts in the process of touching the switch lightly. Contacts depend on size (the bigger the better).
Second, it depends on the material. At present, there are three main types of contacts: silver-nickel alloy, silver-cadmium alloy and pure silver. Silver-nickel alloy is an ideal contact material at present. It has good electrical conductivity, hardness and is not easy to oxidize and rust.
Silver-cadmium alloy contacts are also good in other aspects, but cadmium belongs to heavy metals. On the one hand, cadmium is harmful to human body, on the other hand, the fusion of silver is not ideal. Small particles of cadmium metal will form on the contact surface, and arc may be pulled out when conducting electricity. Pure silver is not suitable for contact. It has good electrical conductivity, but it is soft and easy to oxidize (like silver jewelry will turn black after a long time). Soft texture, more contacts on the switch will deform; oxidation rust, conductivity will be much worse, rust is easy to heat, it is easy to burn contacts.
Third, look at the light touch switch structure. Nowadays, they are mostly large panels, and their appearance and feel are better than those of thumb. The biggest problem with thumb type is that it is easy to jam, because the moment is relatively short, the switching action amplitude is relatively small, the spring is a little Microsoft or a little too hard, may cause the switch to jam.
These are some requirements and precautions when selecting the light touch switch. At the same time, the contact size is also a very important issue.
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