Protective circuit breaker

摘要

Known protective circuit breakers which respond to overcurrent have a thermistor (3) with a positive temperature characteristic as well as a parallel resistor (5), which is connected in parallel therewith. A switch which is arranged in series with this parallel circuit interrupts the circuit in the event of an overcurrent and results in the PTC thermistor (3) returning to the low-resistance state again. A compact protective circuit breaker unit which is easy to manufacture and assemble (install) is obtained according to the invention in that the parallel resistor (5) is a resistance body (13) which can be pressed into a mould and is made of a conductive ceramic material consisting of a mixed oxide, for example of LaMnO3. <IMAGE>