Abstract: The present invention relates to an electrode system for detecting residual chlorine in water. Active electrode of the device was prepared by a very simple method in which the antimony pellet was prepared using high pressure and sintering at higher temperatures. An advanced version of the same was prepared by electrochemical coating of antimony on copper rods. A combination of thin platinum wire and antimony coated electrode was used to test residual chlorine in water. The said device responds to the changes in residual chlorine concentrations in water in the range of 0-4 ppm. To increase the accuracy of the electrode system two platinum-antimony electrodes were used by adding an inline cartridge of oxidant absorptive material. This method was used for the sensing of pH using the same electrode system and further pH compensation of chlorine signal.