Локальный датчик протечки.

The new flood detecting device is able to sense the presence of water in an environment.
It is generally used to protect against flooding in computer rooms, offices, laboratories, special environments. It is made up of a detector (normally fitted on the electrical panel) and a sensor (installed in the position being checked).
When the sensor is wet by the water, the alarm is automatically activated on the detector, switching the status of the relay.