Time savings and simplified management are the central advantages of Irrigation automation. If an Irrigation controller or an electro-valve is equipped with an automatic switch unit based on a sensor for soil or substrate, the crop is allways optimally irrigated but unnecessary and potentially costly water applications are not taking place.

Depending on the availability or absence of electrical power on site and the type of soil moisture based switch unit the use of an irrigation controller is optional or necessary. A professionally planned irrigation automation based on soil- or substrate moisture consists of the elements Soil moisture based switch unit, electro valve and irrigation controller (in some situations not compulsory).

A - Mode of operation - with irrigation controller

The irrigation controller is programmed on a time based schedule, for exaple irrigation 4 times per day for 15 minutes. If a soil moisture based switch unit is present, the irrigation controller checks every time before a water application is allowed the status of soil moisture. In case the soil or substrate is still wet enough this individual irrigation event is blocked, and does not take place. The system waits in this situation until the next water application is scheduled, when this routine is repeated.
Switch units which can be used this way are marked with A.

B - Mode of operation - direct control with switch Tensiometer (24V AC only)

The switch Tensiometer permanently controls the water availabilty in soil or substrate, and is wired to the electro valve. At a certain point of water availabilty or soil moisture potetianl, the switch point, an electrical contact is closed, and the electric valve is supplied with power, and opens the water flow. As soon as the soil moisture potential is again below the switch point, the valve closes again. A central advantage of this technique are low cost and a straight foreward apporach.
Switch units which can be used this way are marked with B.