Research of processes on contact surfaces of low-voltage swiching devices

Abstract

In operation of electric systems, its constituents, cables, switching devices are heated up by the electric current. As the current is switched on, all the heat received by the conductor is spent to increase its temperature which in the absence of cooling rises linearly. In reality, the heating is followed by loss of the heat to the environment. And the rate of this loss increases with increase in the difference of temperatures of the conductor surface and the environment. The rate of temperature increase in the cable cores slows down, temperature tends to the highest extreme value providing for thermal balance. The influence of thermoelectric effects on heating of low-voltage switching devices caused by communication between the thermal and electrophysical phenomena in electric contacts is considered. Research of the resistance size of contact groups tightening which depends on the contact surface actual platform radius and the switching device current are provided.