Faulty current protective circuit breaker - has summation transformer with additional short circuit winding with specified resistance

摘要

The automatic protective circuit breaker for faulty currents has a summation current transformer whose care carries a secondary coil which is connected to the excitation winding of a tripping device, affecting the switch lock. The core carries a second winding with a specified resistance value. This additional winding is in the form of a short circuit coil (20), whose resistance value is matched to the tripping current. The assembly enables the employment of summation current transformer with a high secondary output. The tripping device (11) acts upon the switch lock (12) via a coupling rod (14). A testing circuit (16) with a testing push-button (15) complete the assembly.