Method and apparatus for the determination of switchgear-specific data at contacts in switchgear and / or for the determination of operation-specific data in order switched network

The invention relates to a method in which the contact spring action at the break is detected, in particular for earthing contacts, as a replacement criterion for the erosion of contacts. Erosion can be determined by measuring the change in contact spring action during the switching off process, and converted to give the residual life of the contacts. This requires precise measurement of the armature path from the beginning of the armature movement to the beginning of the contact opening. In accordance with the invention, the switching conditions in the switchgear and in the electric network can also be detected from the signals used for determining the contact spring action.