The WATERMARK Monitor family of data loggers are devices that automatically take soil moisture readings. This reading history provides a vivid picture of the soil moisture profile your irrigation practices have created.

Data downloaded from a WATERMARK Monitor can be evaluated to determine ways to improve the irrigation scheduling for optimum results. Individual sensor readings display on the Monitor and can be taken at any time manually, allowing you to make on the spot checks as necessary for scheduling purposes while periodic readings are being taken to record the performance history. Record soil moisture, soil temperature, switch positions, and rain gauge counts for an accurate record of the performance of your irrigation schedule. IRROMETER switching pressure gauges are used as switch position sensors to indicate when the system pressure is on and off to display the irrigation events. Temperature compensation of the soil moisture reading is automatic by using one or more temperature sensors or programming a default value. The IRROMETER Model RSU (4-20mA transducer) can also be read (wiring adapters and auxiliary sensor power required). Spring-loaded terminal strips are provided for sensor connections, which allow for easy installation and never need tightening. Included wire entry strain relief connectors keep enclosure sealed and retain wires. Data can be downloaded directly to a computer via USB, Serial, with a PDA or via wireless telemetry.

900M Data Logger

The WATERMARK Monitor is the standard wired version of our data logger, providing users with a reliable, simple, and effective means of collecting information.

WATERMARK Monitor Features:

  • Automatically reads sensors at a selectable interval
  • 8 sensor capacity, can read:
  • WATERMARK Soil Moisture Sensors
  • Temperature Sensors
  • Tipping Bucket Rain Gauges
  • 4-20 mA Current and 0-5 Voltage output IRROMETER Tensiometers (RSU-C and RSU-V with Adapter)
  • On/Off switch states
  • Temperature compensation
  • WaterGraph Software included (MS Windows only)
  • In-field display of current and recent readings
  • Download history to a computer
  • Outdoor mount
  • 9 Volt battery included
  • Complete with 8 sensors (1 Temperature & 7 WATERMARKs)
  • Weatherproof enclosure with two strain relief fittings for wiring connections, predrilled mounting hole pattern
  • USB and Serial download ports

The WATERMARK Monitor is user programmed for the individual characteristics of the site to be monitored:

  • A unique location name
  • The time interval to automatically take readings, from once every minute to once every day
  • A unique name for each sensor being read
  • The date and time you want readings to begin
  • The selection of sensor type for each input port

Stored readings are downloaded to a computer for display. Other display options are available. The software, included with the WATERMARK Monitor, is used to set up your individual site profile, launch the data-logger, download recorded history and graphically display the results. The data file created can also be opened by some spreadsheet or graphing programs, like Microsoft Excel®.

409 900M Specification Document
900M Installation and Operating Instructions

WaterGraph 3.41 Software for 900M Data Loggers

For further documentation information regarding the WATERMARK Monitor 900M, please click here

For WaterGraph software downloads, please contact us at

The WaterGraph Data Shuttle (900-DS) is a device that downloads collected data from either 900M or the No Longer Available 950R Series WATERMARK Monitors and stores the data on a multimedia card (MMC). The card can be removed from the Data Shuttle, inserted in to a reading device connected to a PC, and read by WaterGraph software for analysis of the recorded data.

WaterGraph Data Shuttle Features:

  • Easy to use
  • Convenient

The Data Shuttle Includes:

  • Data Shuttle with Battery
  • Cable
  • Storage Pouch
  • Instructions
  • USB Multimedia Card Reader and Software
  • Multimedia Card (MMC)

900-DS Data Shuttle Instruction Manual
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Data access options for both the 975 IRROmesh Wireless Monitors and 900M Wired Monitors improve productivity by bringing important soil moisture information to you. Remote areas and multiple crop locations can be monitored from a central location. The remote access components are modular in design and can easily be added to an existing Monitor installation. World-wide access to 900M or 975 data is simple with the use of a Cellular Gateway and the Internet.

IRROmesh Solar Powered Wireless Radio Features:

IRROMETER Company, Inc. | Phone: 951-682-9505 | Fax: 951-682-9501 | |

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