This article summarizes how the Zirkon® DIS Total sensor differs from the Zirkon® DIS sensor, and some important things to keep in mind about the total chlorine measurement.
Unlike the Zirkon® DIS sensor, the Zirkon® DIS Total sensor measures both hypochlorous acid (HOCl) and the hypochlorite ion (OCl-). Using these parameters with a total-chlorine specific electrolyte, the Zirkon® DIS Total sensor generates a total chlorine measurement, which includes both free chlorine and combined chlorine (chloramines and organic chlorine compounds). The sensor does not distinguish between chloramines and other organic compounds.
Because the Zirkon® DIS Total sensor responds to both HOCl and OCl-, it has a much smaller pH influence than the Zirkon® DIS sensor. At this time, Kuntze does not offer a pH compensation function for the Zirkon® DIS Total sensor. We have found that the pH influence on the total chlorine measurement is negligible in most applications.While the Zirkon® DIS sensor should only be used up to pH 8.5, the Zirkon® DIS Total sensor can be used up to pH 10. You can learn more about using the Zirkon® DIS Total sensor for free chlorine at high pH here.
Temperature compensation for the Zirkon® DIS Total sensor is identical to that of the Zirkon® DIS sensor. Most applications do not need compensation at all, but temperature compensation is offered.
One important difference between the Zirkon® DIS sensor and the Zirkon® DIS Total sensor is the polarization time required before calibration. The Zirkon® DIS sensor only requires about 10-15 minutes to come to electrical equilibrium after installation before it can be calibrated. Due to its design, the Zirkon® DIS Total sensor must reach both an electrical and a chemical equilibrium. Thus, we recommend waiting at least 30 minutes after installing a Zirkon® DIS Total sensor before calibration. You can learn how to calibrate your Zirkon® DIS Total sensor here.
If you have any questions about the difference between the Zirkon® DIS Total sensor and the Zirkon® DIS sensor, please contact a Kuntze representative or submit a ticket.