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Water Treatment Controller W900 Series From Walchem Corporation

USA Toll Free: 1-800-730-0302 Tel: 416-240-1920 -

W900 Water Treatment Controller

The Next Generation of Powerful Control

Connect with the Walchem W900 Series controllers and enjoy unparalleled versatility in maintaining your water treatment options.

Now with expanded new capabilities:

  • Powerful Control

  • Flexible Programming

  • Online Access

  • Easy Setup

  • Great Value

Get more power over your water treatment processes by connecting with your Walchem representative today.

Summary of Key Benefits:

  • Large touchscreen display with icon based programming makes setup easy

  • Universal sensor input provides extraordinary flexibility; the same controller can be used with almost any type of sensor needed

  • Four I/O slots allow complete flexibility in adding additional sensors, analog inputs and analog outputs

  • Multiple language support allows simple setup

  • Eight replay control outputs allow the controller to be used in more applications

  • Economical wall-mount package for easy installation

  • On-screen and web page graphing of sensor values and control output status

  • Complete flexibility in the function of each relay:

    • On/Off Setpoint
    • Time Proportional Control
    • Pulse Proportional Control (when purchased with 4-20 mA or pulse solid state opto outputs)
    • Flow Proportional Control (when purchased with 4-20 mA or pulse solid state opto outputs)
    • PID control (when purchased with 4-20 mA or pulse solid state opto outputs)
    • In-Range or Out-of-Range activation
    • Probe wash
    • Timer-based activation
    • Activation based upon the state of a contact closure
    • Timed activation triggered by Water Contactor / Paddlewheel flow meter’s accumulated total flow
    • Activate with another output
    • Activate as a percent of another output’s on-time
    • Alarm
    • Spike Set Point
    • PPM Volume
    • Target PPM
    • For Cooling Tower and Boiler applications:
         • Biocide Timer
         • Boiler blowdown on conductivity using intermittent sampling

  • Datalogging

  • Email Alarm messages, Datalog reports or System Summary reports

  • Ethernet for remote access via the Internet, LAN or optional Modbus/TCP

pdf W900 Controller Brochure

pdf W900 Manual

pdf W900 Modbus Manual


About Us

Metex Corporation Limited has been providing superior products and services to the process control, chemical treatment, waste water, industrial and manufacturing industries for over 25 years. It is our goal to continually provide our customers with the best possible equipment, technology, and service.


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Dataloggers, sensors, pumps, recorders, hand held instruments, flow instrumentation, level controls, valves, instrumentation, containers, tanks, transmitters, data loggers, digital indicators, mixers and agitators, pressure intrumentation, analyzers and controllers for a variety of industrial applications such as water quality, pH/ORP and more.

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Water Analyzers and Controllers, Wireless Products, Corrosion Monitoring Equipment, Cooling Tower and Boiler Controllers, a wide variety of Pumps, Valves, Dataloggers and Recorders, HVAC, Instrumentation, Skids and Systems, Containers and Tanks from world leading manufacturers are products you will find on this site.

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