Protective Circuit Breakers

Eaton launches its SmartWire-Darwin Module for the PKE motor protective circuit breakers, with electronic wide range overload protection. These circuit-breakers measure the current rise via the integrated current transformer in the trip block, and evaluate it via a special electronic circuit which sends a pulse via an actuator system to the switch mechanism. The voltage supply of the electronic circuit is implemented via a transformer. The opening time depends on the ratio of the tripping current to the setting current and is stored in the form of a long-time stable tripping characteristic curve. They operate with a larger current transfer ratio. In this way, the device has a wide current setting range in the ratio 1:4.