This is N/C type. In this the electrical circuit is ON when magnet is away from sensor(door in open position).
Used in kitchen cabinet etc. to make led light ON when cabinet door opens.
The sensor alone can be connected only in low power ( less than 12 W) dc circuits. it can not directly connect to 230 v ac circuit.
For that you will have to use a relay along with this sensor. we have the relay fitted version also for 230v ac.