Application Note

pH Control Systems

Source: Hach

Different types of applications require different pH control systems. This technical bulletin describes six basic types of pH control systems and outlines the operating principles of each. It is intended to help match applications with the most suitable pH control system.

This type of control system uses an on/off relay controller for "batch" processing. The system operates as follows:

  1. Process solution is pumped into a tank until full.
  2. Agitation or mixing begins and chemical is added until desired pH is reached. The relay controller switches the chemical addition pump (or solenoid valve) on/off.
  3. Process then flows out or is pumped out of tank.