PC2100A Programmable Controller

A Fully Programmable Controller

Specifically designed for Australia, the CHEMTROL® PC2100A is a simple and reliable programmable controller that features automatic maintenance of water chemistry:

  • pH to control liquid acid and/or CO2 gas,
  • Free available chlorine (ppm) to control sanitiser level in ppm or mg/ per litre,
  • Total chlorine (ppm) to control high combined chlorine (Chloramine),
  • TDS to control solids level and to avoid high chlorine consumption,
  • ORP to have sanitizer reading/reference and/or control backup.

Programmable super-chlorination and/or chemicals savings cycles with display of the Langelier Saturation Index. The controller main screen display includes large 8-lines to enable the operator supervise all process functions at a glance and to quickly respond to any changing condition.

The CHEMTROL® PC2100A controller operates like a computer with multi-line screen displays and direct access to all menus and submenus. The front panel keypad is used to move up and down each menu and enter or exit the submenus. All operating functions can be easily modified from the keypad, including sensor calibration, control setpoints, alarm levels and the programs for super-chlorination and chemical savings.

Standard Features

  • Chemical Automation available with pH, ppmF, ppmT, ORP, TDS and Temperature,
  • Free and/or Total chlorine sensors to control sanitiser level in ppm or mg/ per litre.
  • pH CONTROL with choice of acid or base feed,
  • ORP control of sanitizer (chlorine or bromine) and/or oxidizer activity – compatible with all common sanitizers and oxidizers,
  • TDS control with optional dump valve for water replacement,
  • Programmable SHOCK TREATMENT and CHEMICAL SAVINGS cycles,
  • Programmable PUMP programs with water meter control and alert ,
  • Large 8-line LCD DISPLAY for easy operation,
  • LANGELIER SATURATION INDEX for water balance,
  • Flow Cell Assembly (FCA) with safety flow switch,
  • Sensor cleaning with programmable acid wash control,
  • Remote alarm,
  • AUTOMATIC DATA LOGGING for up to 999 tests
  • Micro SD port for easy program updates and data logging

PC2100A Technical Specifications

Free Chlorine Control (PPM)0 to 10 ppm with direct reading in PPM or mg/l
Total Chlorine Control (PPM)0 to 10 ppm with direct reading in PPM or mg/l
pH Control0 to 14, Set-point for acid or base feed
TDS Control0 to 20,000 mg/l with optional dump valve
ORP Control200 to 999 mV, Set-point for oxidizer or reducer
Shock TreatmentProgrammable shock treatment and chemical saving cycles
Temperature ReadoutFrom -18 to 60 C
Langelier IndexCalculated from pH, Temp, Total Alkalinity and Calcium Hardness. Water Balance display
Sensor Calibration1, 2 or 3 points
Control ModesOff, Manual, Automatic, Timer, ON/OFF or Proportional Feed
Automatic Data LoggingOn-board memory for up to 999 tests
AlarmsHigh/low, out-of-range, run time and overfeed
Visual, audio and external alarms
Patented Probe Alert SafeguardDynamic probe testing with sensor failure warning
Mechanical34 x 29 x 17 cm, Rain and splatter proof NEMA type 4x Cabinet
Electrical10 A 110/230 V with selector switch,
All output and alarm relays 5 A
Warranty5-year on electronics warranty


  • Heater control with dedicated 5 amp. relay output.
  • CHEMTROL® web-server communication – remote monitoring and control with identical duplicate screens technology. True duplex remote operation via Ethernet cable, WIFI, or 4G/5G router with sim-card data subscription.
  • Modbus/BACnet protocol for Building Management System communication (BMS).

PC2100A Installation 

We want to make the installation of CHEMTROL® controllers as simple as possible. This is why we have everything mounted onto a customised assembly manifold ready for connection. This assures proper water sampling around the sensors and makes for a hassle free installation that minimises the integration work needed to get your water treatment system up and running.

PC2100A – Bypass line assembly

Dual ppm control, Free & Total chlorine sensors with pH, ORP, TDS and Temperature

  • Controller wiring: a choice of hardwired dosing pumps or GPOs ready for dosing equipment connection.
  • Flow Cell Assembly (FCA) with clear acrylic flow cells for dual chlorine sensors (ppm). 2x flow control valves, water sample valve, safety flow switch and probes holder fitting.

-Controller assembly : grey PVC backboard 600×400 mm.
-By-pass line assembly : grey PVC backboard 600×500 mm.

PC2100A Operation

The 8-line Display Screen of the CHEMTROL® PC2100A Programmable Controller gives direct access to all the menus and sub-menus. Navigation between the menus and inside the menus is easily accomplished with the four directional arrow keys. Numerical settings can be changed with the ten-key keypad.

The ORP MENU includes selection of the control mode (Off, Manual, Auto or Timer), sensor calibration (1, 2 or 3 points), set-point level, high and low alarms, shocking and chemical saver programs. It also displays the run time for the current feed event and cumulative run time. Shock treatment can be initiated manually or under programmable weekly or multi-weekly schedules.

The SANITIZER MENU is used to control the chlorine or bromine level in terms of sanitizer concentration (parts per million or milligrams/litre), obtained from the optional PPM sensor. The sanitizer concentration readings can be calibrated to account for the effect of cyanuric acid stabilization. Super-chlorination can be initiated manually or under programmable weekly or multi-weekly schedules.

The pH MENU is used in the same way to select the pH control parameters using either acid or base feed or both. It also includes an Acid Wash program for periodic injection of an acid rinse solution to clean the heads of the sensors.

The TDS MENU is used to set automatic dumping (bleeding) of water when the dissolved solid concentrations becomes too high, selecting either a Conductivity or a TDS control setpoint to activate the dump valve. Refilling of water can be done simultaneously with a level control activated valve.

The Langelier Index calculates the saturation condition from the pH and Temperature sensor inputs and from manual data entry for Alkalinity and Calcium Hardness. The water saturation condition is constantly displayed on the Main Screen as either “OK”, “Scaling” or “Corrosive” using standard Langelier Index limits. If a scaling or corrosive condition develops, it is immediately indicated with a flashing display on the Main Screen. “What if” analyses can be run at any time by manually entering different values for alkalinity, calcium hardness, pH and temperature.

The TEMPERATURE MENU is used to calibrate the temperature sensor using 1, 2 or 3-point calibration and to set high and low alarms. Temperature Sensor readings can be displayed either in degrees Fahrenheit or Celsius.

The SETUP MENU is accessed from the Main Menu by pressing the down arrow after reaching the bottom of the screen. This menu is used to modify the configuration parameters for initialization, operations and communications from their initial default values. These values can be changed at any time or restored to the original default values.

Find out more: Control Proficiency

Remote Monitoring & Control

Our range of programmable controllers all have remote access capability, so you can control and monitor your facility 24/7.

With the remote operation function any number of facilities can be controlled and monitored from your computer, or via our mobile App. From a computer simply login directly via your browser using our web-server where the controller display is mirrored on your computer.

True duplex operation that allows real-time control and troubleshooting of all operating functions, including status reports, trend graphs and automatic alerts by email or text messages. You can also access and control your controller via our dedicated app, available for Android and Apple devices.

In terms of connecting your controller, this can be achieved via a wired Ethernet cable, WIFI signal, or by using a wireless connection with a compatible 4G or 5G router.

Find out more: web-access options.