AC Contactor Tungsten Contacts

AC contactor is applied tungsten copper or tungsten iron contact as main connecting parts. AC refers to alternative current. Why tungsten contacts are selected for the contacts of AC contactors? Tungsten as raw material made contacts are with superior properties.

Contacts made with tungsten sheet and iron or copper leg are with properties of high temperature resistance, which can effectively avoid melting due to the increase of external temperature, so that the contact performance of the circuit can be improved.

The W contact has superior thermodynamic performance and better heat dissipation performance, which can significantly extend the single working time of the AC contactor.

Contact applied tungsten, is used purity over 99.95%, so it is with a low impurity content and a smooth surface.

tungsten contacts image

AC contactors are commonly used to eliminate the arcs generated by the moving and static contacts during the opening and closing process; the working principle is to use electromagnetic force and spring elastic force to achieve the connection and breaking of the contacts, so there are two working states, namely Power-off state (release state) and energized state (action state).

In many cases, Alternative Current contactor contacts will malfunction due to overheating or burns. How does the overheating phenomenon occur? The contactor is working in a place where the ambient temperature is too high for a long time, which will naturally increase the temperature of the contactor.

AC contactor image

The cross-sectional area of ​​the place where the contact is poor is small, which causes the resistance in the place to be larger, and the passing current will be larger, the power loss will be higher, and the heat generated will be more, which will cause the temperature to rise. Burn the wires. Spark discharge occurred at the contact point. Spark discharge will produce high temperature, which is mainly because the periodic decrease of current leads to frequent spark discharge at the contact point and rapid temperature rise.

After the introduction of the above content, we also have a certain understanding of why the temperature of the Alternative Current contactor will rise. Nowadays, in order to prevent the contacts from being burned, tungsten made contacts are used more widely as the contacts of AC contactors.

 

 

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