FullStop™ Depth of Placement

The depth of placement depends on the irrigation method and the frequency of irrigation. Detectors are placed deeper for drip compared to sprinkler irrigation. A daily irrigation interval requires shallower placement than a weekly interval.

Depth Marker

The indicator pops up when the wetting front has moved about 10 cm below the rim of the funnel, labeled "0" in the diagram on the right. The position of the lock up ring is the approximate depth of measurement.

The shallowest depth the detector can be located is 15 cm, or 5 cm of soil above the rim of the funnel. The deepest depth with one extension tube is 20 cm, with two extension tubes is 50 cm and with three extension tubes is 80 cm. Use the joins and ridges on the extension tubes to check depth as shown in the diagram on the right. We do not recommend you use more than three extension tubes.

Placement For Drip, Furrow & Sprinkler Irrigation

The diagrams below suggest where to install detectors for drip, furrow and sprinkler irrigation. With experience, the placement depths can be altered to suit local conditions and management styles.

Drip Irrigation

The detector must always be placed directly under a dripper. Suggested depth for the shallow detector is 30 cm and for the deep detector is 60 cm

Deeper placement is required for widely spaced drippers or long irrigation intervals. Shallower placement suits closely spaced drippers, frequent irrigation or shallow rooted crops.

It is common for detectors to respond quickly under drip because all the water is being concentrated around the dripper, with dry soil betweeen drippers. In such cases less water should be applied more often.

Sprinkler Or Microjet Irrigation

Wetting patterns tend to be shallower under sprinkler irrigation than drip or furrow irrigation.

Suggested depth for the shallow detector is 20 cm and for the deep detector is 40 cm. Note that it usually takes 20 mm or more of irrigation to activate a detector at 20 cm (depending on soil type and on how dry the soil is before irrigation).

For sprinkler systems that apply small amounts of water each day or second day (e.g. microjets or centre pivot) depths of 15 cm and 30 cm are more suitable (5 cm and 20 cm to the rim of the funnel). Detectors will usually not be activated by applications under 15 mm, unless the soil is quite wet before irrigation.

Furrrow Irrigation

Detectors should be positioned half under the furrow and half under the bed with the extension tube rising through the shoulder of the bed.

Suggested depth for the shallow detector is 20 to 30 cm and for the deep detector is 40 to 60 cm (from the base of the furrow). Deep rooted crops with less frequent irrigation would require deeper placement.