MAS-1 4-20 Milliamp Soil Moisture Sensor Description：

User's Manual

▶ Affordable current-based soil moisture sensor

The MAS-1 4-20 milliamp soil moisture sensor is the first current-based sensor to use METER’s trademark 70 MHz technology. This sensor offers a standard 4-20 milliamp output that is common with PLCs and irrigation controllers. With the 4-20 mA interface, cable lengths over 250 feet are possible.

▶ Research-grade accuracy

The MAS-1 soil moisture sensor determines volumetric water content (VWC ) by measuring the dielectric constant of the media using capacitance/frequency domain technology. The sensor uses a 70 MHz frequency, which minimizes salinity and textural effects, making the MAS-1 accurate in almost any soil or soil-less media. Factory calibrations are included for mineral soils, potting soils, and rockwool.

▶ Low cost individual sensors for large sensor networks

The MAS-1 delivers research-grade soil moisture accuracy at a price that makes large sensor networks economically practical. You can adequately characterize your site with sensors at multiple depths and locations, even if you’re on a tight budget.

MAS-1 4-20 Milliamp Soil Moisture Sensor Specification：