The FC (Free Chlorine) membrane probe and the TC (Total Chlorine) membrane probe are extremely accurate probes that only need to be and must be serviced every 6 months.
The FC probe is suitable for pool operators who are more comfortable working with FC than ORP.
At a pH of 7.2 the probe is registering 100% Hypochlorous acid as molecular. Most bools operate at a pH from 7.4 to 7.6. At pH of 7.5 the probe is reading at what looks like 97%. That's pretty good. Your (usually) required morning DPD test result will confirm its accuracy after taking the testing errors into account.
The TC probe is an essential addition to the FC probe for indoor pools. Indoor pools need to monitor their Combined Chlorine (= TC – FC) levels daily, especially if the Centre has poor air circulation. Combined chlorine is considered hazardous for workers who are working in such a pool area for extended periods of time.
TARAline CS4MA-200 Free Chlorine Sensor
pH range: 4 to 9
FC range: 0.5ppm to 10ppm
Output: 4-20mA
TARAline CP4.0 Total Chlorine Sensor
pH range: 4 to 12
TC range: 0.05ppm to 10ppm
Output: 4-20mA
