M173 Soil moisture sensor, 12 V/DC

This sensor switches on your garden irrigation pump or the solenoid valve on when the soil is dry, and turns off when enough moisture is in the soil.

The measuring head is buried in the soil at the depth, where it is supposed to measure and is connected via a cable to the base unit. There is a 2-m cable included, but the sensor cable can be extended using a conventional 2-pin cable up to 20 m. The device is operated using a commercially available plug-in power supply (12 V/DC stabilized, > 130 mA, jack 3.5 mm). If the garden is to be watered only at certain times of day or days of the week, then plug the power supply into a commercially available timer and program this accordingly. If the soil moisture sensor gets power from the power supply unit, it will start to work.

Operating sequence: After switching on the operating voltage, the soil moisture is measured. If the soil is too dry, the connected pump is switched on for 18 - 30 minutes. If the soil is sufficiently wet, the device goes into "Pause" mode for approximately 18 - 30 minutes and then makes a new measurement. This continues in an endless loop until the operating voltage is switched off.

Technical data Operating voltage 12 V= stabilized > 130 mA, 3.5 mm jack socket Display 3 LED's: "On" ... "Off" ... "Pause" Switch contact potential-free relay contact 1 x On max. 3 A (up to 25 V or also 230 V~, see description) Connections screw terminals Time delays 18 - 30 minutes each Infinitely adjustable threshold The base must be mounted in a dry area. Soil moisture sensor diameter dimensions approx. 30 x 64 mm plus 2 galvanized metal pins approximately 4 x 40 mm Base unit dimensions approx. 72 x 50 x 28 mm (without mounting brackets)