Sensor selection
Choose a sensor with a compatible signal level or dry-contact output for the NetRelay digital input. Follow manufacturer requirements for supply voltage, output type, and cable length, and apply electrical safety rules in wet areas.
Alarm logic
One input change can trigger both a local event and a Home Assistant notification. If cable disconnection must also appear as an alarm, design the normal-state logic accordingly. Reduce false alarms through sensor placement rather than excessive delay.
Valve control
For a motorized shutoff valve, verify voltage, current, and control method; use a suitable contactor or interface relay where required. Define manual operation and the valve position during power loss.
Periodic testing
Test the sensor regularly according to its instructions. Verify notification delivery, relay action, and manual recovery. This automation does not replace maintenance or insurance requirements; it adds an early-warning layer to building procedures.