It is studied how to reach higher switching capacities by a series and parallel connection of fast and low-current contacts. Naturally given effects of these contacts, like the minimum voltage of a steady arc after contact separation and the withstand voltage after arc extinction, can be multiplied by a series connection of contacts in a path. Paths are added in parallel to a so-called matrix to obtain a higher current capacity. Basic experiments and a model for the calculation of such matrices with a great number of contacts show the difficulty of current commutation between the parallel paths due to the jitter at contact separation. This commutation is accelerated by switching in an area with a negative voltage-current characteristic of the burning arcs. Experiments show that in contacts having gaps in the range of some mm and a current capacity of some amperes, this negative characteristic can be avoided, and that the arc voltage is determined uniquely by the gap of the contacts. These findings are fundamental for the optimization of such switches as part of a hybrid system or for the realization of a matrix as self-contained switchgear.
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