W900 Series Controllers
The W900 series provides reliable, flexible and
powerful control for your water treatment program.
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 sensors, analog inputs, analog outputs and LPR corrosion sensors
> Multiple language support allows simple setup
> Eight relay control outputs allow the controller to be used in more applications
> Eight virtual inputs and eight virtual outputs
> 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 a Water Contactor or 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
• Flow Meter Ratio
• Volumetric Blending
• Disturbance Variable Control
• For Cooling Tower and Boiler applications:
• Biocide Timer
• Boiler blowdown on conductivity using intermittent sampling
Ethernet or WiFi for remote access via the Internet, LAN, or optional BACnet or Modbus/TCP
> Datalogging
> Emailing Alarm messages, Datalog, Graph, or System Summary reports
W900 Specifications
Inputs
Power
100-240 VAC, 50 or 60 Hz, 13A max Fuse: 6.3 Amp
Outputs
Powered Mechanical Relays (0-8 model code dependent)
Pre-powered on circuit board switching line voltage
Four relays are fused together as one group, total current must not exceed 6.3A (resistive), 1/8 HP (93W)
Dry Contact Mechanical Relays (0-8 model code dependent)
6 A (resistive), 1/8 HP (93W)
Dry contact relays are not fuse protected.
Pulse Outputs (0-4 model code dependent)
Opto-isolated, solid-state relay, 200mA, 40V DC
VLOWMAX = 0.05V @ 18mA
4 – 20 mA (0-16 model code dependent)
Internally powered, 15VDC, Fully isolated
600 ohm max resistive load
Resolution 0.0015% of span
Accuracy ± 0.5% of reading
Sensor Input Signals (0-8 depending on model code)
Contacting Conductivity: 0.01, 0.1, 1.0, or 10.0 cell constant, or
Electrodeless Conductivity or
Disinfection or
Amplified pH, ORP, or Ion Selective Electrode which requires a preamplified signal. ±5VDC power available for external
preamps. Walchem WEL or WDS series pH/ORP sensors recommended.
Each sensor input card contains a temperature input.
Temperature: 100 or 1000 ohm RTD, 10K or 100K Thermistor
Analog (4-20 mA) Sensor Input (0-24 depending on model code)
2-wire loop powered and self-powered transmitters supported
3-wire and 4-wire transmitters supported
All Channels fully isolated, input and power
Channel 1, 130 ohm input resistance, Channel 2-6, 280 ohm input resistance
Available Power: Isolated 24 VDC ±15% supply per channel. 1.5 W (62.5 mA maximum for each channel)
Digital Input Signals (12):
State-Type Digital Inputs
Electrical: Optically isolated and providing an electrically isolated 12V power with a nominal 2.5 mA current when the digital
input switch is closed. Typical response time: < 2 seconds. Devices supported: Any isolated dry contact (i.e. relay,
reed switch). Types: DI State
Low Speed Counter-Type Digital Inputs
Electrical: Optically isolated and providing an electrically isolated 12V power with a nominal 2.5 mA current when the
digital input switch is closed, 0-20 Hz, 25 msec minimum width. Devices supported: Any device with isolated open
drain, open collector, transistor or reed switch.
Types: Contacting Flowmeter
High Speed Counter-Type Digital Inputs
Electrical: Optically isolated and providing an electrically isolated 12V power with a nominal 2.5 mA current when the
digital input switch is closed, 0-500 Hz, 1.0 msec minimum width. Devices supported: Any device with isolated open
drain, open collector, transistor or reed switch. Types: Paddlewheel Flowmeter
Outputs
Powered Mechanical Relays (0-8 model code dependent)
Pre-powered on circuit board switching line voltage
Four relays are fused together as one group, total current must not exceed 6.3A (resistive), 1/8 HP (93W)
Dry Contact Mechanical Relays (0-8 model code dependent)
6 A (resistive), 1/8 HP (93W)
Dry contact relays are not fuse protected.
Pulse Outputs (0-4 model code dependent)
Opto-isolated, solid-state relay, 200mA, 40V DC
VLOWMAX = 0.05V @ 18mA
4 – 20 mA (0-16 model code dependent)
Internally powered, 15VDC, Fully isolated
600 ohm max resistive load
Resolution 0.0015% of span
Accuracy ± 0.5% of reading
