PH Controller

Libratherm offers PID Controller for ON LINE monitoring and controlling of pH or ORP or Conductivity value in the continuous process. The controller can be interfaced with the pH / ORP / Conductivity sensor to display the pH value in the range of 0.00 pH to 14.00 pH or ORP /Conductivity value in mV.
Since the signal given by the pH electrode varies with the temperature, automatic temperature compensation (ATC) facility is in-built in the instrument to read pH value more accurately without manual adjustments. This feature is available in model PD-5000.
The controller gives direct / reverse dc pulse PID output with settable dead band for the metering or dosing pump to control quantity of both acid and base levels in the chemical process, water purification or effluent treatment plants. The normal pulse rate is 100 pulses per minute. The dual direct / reverse 4 – 20 mA is also available for actuator accepting direct analog signals. The retransmission output of (4-20)mA proportional to pH/ORP level is also made available for the recording purpose. The controller is available in both standard and weather proof enclosure.
For interfacing low level signals from ORP/pH/Conductivity sensors, Libratherm offers signal convertor/isolator module for generating proportional (4-20)mA signal for long distance transmission of the measured value.