HANNA PCA312-1

The HANNA PCA 300 series models are chlorine, bromine or iodine and pH, ORP and temperature process analyzers which continuously monitor a sample stream and control the dosing to adjust the chlorine, bromine or iodine content and pH.

From drinking and wastewater treatment to the pool and spa sanitation, the monitoring of chlorine, bromine or iodine levels has an important bearing on public health as well as ROI and efficiency for heating system and industrial applications.

The PCA 3X0 series monitors the free chlorine or total chlorine in the 0 to 5.0 mg/ L range; The PCA 3X1 series monitors the bromine in the 0 to 10.0 mg/ L range; The PCA 3X2 series monitors the iodine in the 0 to 12.5 mg/ L range;

In the DPD Colorimetric method, N, N-Diethyl-p-phenylene-Diamine indicator and a buffer are mixed with the sample. Free available chlorine oxidizes the DPD indicator reagent at a pH between 6.3 and 6.6 to form a magenta colored compound. The intensity of the resulting color is proportional to the concentration of chlorine in the sample. The purpose of the buffer solution is to maintain the proper pH.

In total chlorine measurement ( free available chlorine plus combined chloramines) , potassium iodide is added. The chloramines in the sample cause the iodide ions to become iodine which reacts with free chlorine to oxidize the DPD indicator. A pH of 5.1 is required for this reaction. Thus total chlorine measurements require a different buffer solution containing potassium iodide. Once the chemical reaction is completed, the optical signal at 555 nm is compared to the signal measured through the sample before the reagents were added. From these measurements chlorine concentration is calculated and shown on the display.

Indicator and buffer reagent bottles are placed directly into the instrument case. With a sampling period of 5 minutes, reagents need only to be replenished about once a month. Since chlorine, bromine and iodine effectiveness is closely tied with pH levels, HANNA has designed our new analyzers PCA 32X and PCA 33X with pH control and temperature and pH control, ORP monitoring and temperature respectively.

PCA 32X and PCA 33X use the HI 1005 pH probe to continuously measure the pH of the sample stream in the range of 0 to 14 pH. The sample temperature is measured in the 5 to 75° C range. pH and temperature are displayed on the front panel, and the pH value is temperature compensated.

PCA 33X uses the HI 2008 platinum ORP electrode to continuously measure the sample ORP value. The pH/ temperature combined sensor and the ORP sensor are placed inside the case, directly in the sample stream