The KIW-3xx* Short - Circuit Relay monitors the current in three-phase networks. It is equipped with 2 limit value relays, whose response values can be set independently of each other, ranging from 0.2 A to 20 A. Separate delay times and switching behaviours are adjustable for each limit value. For the current measurement, which is done via transformers, current transformers, suitable for the adapting to the measurement circuits, are to be provided. The auxiliary voltage and release input ( terminals 1 - 3 ) are galvanically separated from the measurement circuits. The current measurement circuits ( terminals 10 - 15 ) are galvanically separated from each other and from the other electronics.
Special Feature:
The threshold relay 1 can operate as a current-depended delayed overload relay. This behaviour is modelled on the thermal / temporal overload triggering of motor circuit breakers. The KIW-3xx meets the VDE 0108 requirement with 110 % nominal current within a 12-hour interval. This current-dependent overload trigger can be switched off, resp. combined.