Der zeitliche Temperaturverlauf in elektrischen Kontakten
R. Holm has given a simple calculation of the temperature in electrical switching cantacts assuming a spherical symmetry of the effective contact area. Here the present authors give a more precise derivation of the temperature dependence on time assuming a contact model better corresponding to the technical conditions. Thus the effective contact area is assumed to have cylindrical symmetry. In consequence the calculations become more difficult. The equations are solved in terms of the Green functions of the thermal conduction formulae. The authors solve the integrals by numerical methods. These results are compared with the above mentioned simple formulae of Holm and it is shown that there exist strong deviations especially immediately after switching in the current; this temperature rise amounts to about 40% of the previous formulae only.
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