Switching device for e.g. wind turbine, for selectively connecting electrical load to mains power supply, has resistor connected between neutral-potential and local ground potential and serially connected with switch unit

摘要

The device has a resistor (23) connected between a neutral-potential (N) and a local ground potential (PE) and serially connected with a switch unit (K7), where the device is secured over a residual current protective device (RCD). Resistance of the resistor is 1000-2000 ohms, and the switch unit is switched between the neutral-potential and the local ground potential. An earth-leakage circuit breaker (20) is connected with an electrical load (5). An independent claim is also included for an emergency power system for selectively connecting a load to a mains power supply including a mains power supply.