User manual HANNA INSTRUMENTS PCA 331

[. . . ] Instruction Manual PCA 311, PCA 321, PCA 331 Bromine, pH, Temperature, ORP Analyzers w w w. c o m 1 Dear Customer, Thank you for choosing a Hanna Product. This instruction manual has been written for the following: PCA 331 ­ Bromine, pH, temperature, ORP analyzer. PCA 321 ­ Bromine, pH, temperature analyzer. [. . . ] Rec" will set the recorder low limit and "Max. Rec" will set the recorder high limit. The output will be proportional with pH value if the read value is between those limits. The analog output limits could be quickly consulted in one of the pH measuring panel. pH DOSING The PCA 321 and PCA 331 can use ON/OFF or proportional dosing algorithm to stabilize the pH. The analyzer has a relay for acid or alkali dosing and also the 4-20 mA output could be configured as a dosing output. To select the type of pH dosing edit the "pH Menu" - "Dosing Control pH" - "pH Control" line. The available options are Proportional and ON/OFF . The acid or alkali dosing is set in the "pH Menu" - "Dosing Control pH" - "Dosing Type". When "Acid" is selected, the analyzer will dose when the pH value is higher than the setpoint and when "Alk" is selected, the analyzer will dose when the pH value is lower than the setpoint. PROPORTIONAL DOSING The proportional dosing pH Relay off Setpoint algorithm turns on the Proportional dosing dosing relay proportionally with the difference Relay on between the setpoint and measured value. time The equation for determining the time for relay on is: dosing time = (set value - measured value)*Period/Delta delta 42 Note: Note: Note: The analog output will have the value: analog output [mA] = 4 + 16 * dosing time/Period [mA] If the measured pH is lower (or higher for acid dosing) than setpoint minus (plus) delta, the dosing will be continuous until the pH period elapsed. To modify the dosing setpoint, enter the "pH Menu" - "Dosing Control pH" edit the "Setpoint" line. The value must be between 2. 00 and 12. 00 pH. To modify the Delta, edit the "Delta" line. The available values are 0. 1, 0. 2, 0. 3, 0. 4, 0. 5, 0. 6, 0. 7, 0. 8, 0. 9, 1, 1. 5, 2. To modify the dosing time edit the "Period" line. The allowed values are between 3 and 120 seconds. The period is related only to the dosing process. The pH measurement take place with a higher rate. The speed of the analyzer could be modified by changing the regulator period. A new decision regarding the pH dosing is taken only after one period elapsed. [. . . ] Change the reagent or reset the reagent counter. "Br Calibration Old" on LCD and "Br Cal" on SMS Cell calibration is older than 1 months. "Reagent Expired" on LCD and "Reag Exp" on SMS Reagent is older than 3 month. Change the reagent and reset the reagent counter. [. . . ]