Main circuit contacts

Main circuit contacts inspection and maintenance
The number of mechanical operations has a low impact on the life of the main contacts and their overall electrical life. However general information concerning mechanical wear could be of interest.A contact is not necessarily damaged or worn out,just because the surface is rough and discolored. The contacts in the figure
insid e file may look rather inferior but experience has shown that they are better than a new set of contacts. This is because they are ”electrically seated” and make good contact over the entire surface. Based on this it would be completely wrong to change a contact only by judging from the appearance of the surface.
*Interpreting levels of electrical contact wear
*Changing Contacts
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