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→High Electrical Loads
At high electric loads that usually occur in power engineering devices, the switching phenomena are mostly related to arc formation. For most applications, the management of the switching arc is the key problem. Depending on the device, type different requirements are dominant which influence the selection of the contact material. Similar to those in communications engineering, issues related to the switching characteristics and current path have to be considered.
*'''Make operation''' <br />Make erosion caused by pre-close and bounce arcs <br />Welding mainly during bounce arc <br />Mechanical wear mainly through bounce and relative motion<br/>
For very high loads in main power switches and power circuit breakers for medium and high voltage power engineering applications, the most suitable
materials are tungsten based infiltration materials such as W/Cu.
<div class="multiple-images">
<figure id="fig:Typical application ranges for contact materials">
[[File:Typical application ranges for contact materials.jpg|left|thumb|Figure 1: Typical application ranges for contact materials in power engineering switching devices as a function of switching current and voltage]]
</figure>
<figure id="fig:Application ranges for contact materials">
[[File:Application ranges for contact materials.jpg|left|thumb|Figure 2: Application ranges for contact materials in power engineering switching devices as a function of switching current and numbers of operation]]
</figure>
</div>
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==References==