IRROMETER WATERMARK Soil Moisute Sensor 5ft 200SS Monitor Probe_

WATERMARK Soil Moisture Sensor

This sensor responds to changes in soil moisture. As the soil dries, the resistance measurement increases.

This soil moisture sensor is designed to be a permanent sensor and is made with high corrosion resistant stainless-steel electrodes. It will not dissolve over time and is not affected by freezing temperatures. It is extremely easy to install and requires no maintenance.

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In use since 1978, the patented WATERMARK sensor is a solid state electrical resistance sensing device that is used to measure soil water tension. As the tension changes with water content the resistance changes as well. That resistance can be measured using the WATERMARK Sensor.

The sensor consists of a pair of highly corrosion resistant electrodes that are embedded within a granular matrix. A current is applied to the WATERMARK to obtain a resistance value. The WATERMARK Meter or WATERMARK Monitor correlates the resistance to Centibars (kilopascals) of soil water tension.

The WATERMARK is designed to be a permanent sensor, placed in the soil to be monitored and “read” as often as necessary with a portable or stationary device. Internally installed gypsum provides some buffering for the effect of salinity levels normally found in irrigated agricultural crops and landscapes.

Product Features

  • Proven Stable Calibration
  • Range of 0 – 239 cb (kPa)
  • Fully Solid State
  • Will not dissolve
  • Not affected by freezing temperatures
  • Internally Compensated for Commonly Found Salinity Levels
  • Inexpensive
  • Easy to Install and Use
  • Compatible with AC or DC Devices (Specialized Circuit Required)
  • No Maintenance Required

Uses Include:

  • Irrigation Scheduling
  • Water Table Monitoring
  • Leak Detection
  • Agronomy Research
  • Environmental Monitoring