WCAg switch contacts for medium and low voltage.
Our tungsten carbide-silver (WCAg) switch contacts are perfect for your power needs. They reliably switch short-circuit current in vacuum contactors in the 7.2 - 24 kV range, for instance, and have a life of more than a million switching cycles.
We manufacture WCAg compliant with the international standard ASTM B 663-94.
- high arc erosion resistance
- excellent electrical conductivity
- outstanding contact welding resistance
- very low chopping current
Our tungsten carbide-silver contact materials have a silver content between 25 and 60 wt.-%. We would be happy to advise you on the correct choice of material.
Typical properties of our WCAg contact materials:
|Electrical conductivity [m/Ωmm2]||22||35|
We use powder metallurgical techniques to manufacture our composite materials so that we can offer you the ideal combination of different material properties. The most important steps: We mix the input materials and then press and sinter the resulting material. This is the most cost-efficient way of giving our WCAg contact materials the required electrical and mechanical properties. Our manufacturing process allows us to achieve an extremely high material density in excess of 97 %.
Comparison of different contact materials.
The chart shows the chopping current for different contact materials during testing in a 20kA/24 kV vacuum contactor at a maximum current of 630 A.
(Source: F. Heitzinger et al., 15th ISDEIV, Darmstadt, 1992)
Additional typical properties of different contact materials:
|Electrical conductivity [m/Ωmm2]||20||22||35||32||18|