WWD 240 Smart water detector 230 VAC/50Hz/protective contact plug The WWD 240 socket outlet water detector functions as a purely acoustic detector. If ground moisture is detected by the sensor, a loud acoustic alarm sounds and the LED flashes red. After you have added the device to the Smart Live app, it sends a push notification to your smartphone in the event of an incident. Once the sensor has dried out, the device automatically stops and the LED lights up green again.