Hayward CAT-2000 CAT 2000 - Page 18

pH Feed Mode (Acid or Base Feed) P.Fd pH Feed. Selects the condition under which the pH feed output is activated. A Acid (default). pH feed output is activated when the measured pH is greater than the pH setpoint, indicating the need to feed acid to decrease the pH of the water. b Base. pH feed output is activated when the measured pH is less than the pH setpoint, indicating the need to feed base to increase the pH of the water. pH Priority P.Pr pH Priority. Inhibits ORP feed when pH is not within .2 of setpoint. OFF On Off (default). The pH feed and ORP feed decisions are independent of each other. On. The pH Priority feature is enabled. Inhibits the ORP feed output when the measured pH value differs from the pH setpoint by more than 0.2 pH units. For example, when the pH setpoint is 7.5, then the ORP feed output will be enabled when the measured pH value is in the range 7.3 to 7.7; and inhibited when the measured pH is any value outside this range. pH Proportional Feed P.PF pH Proportional Feed. Selects either fixed setpoint or proportional control. OFF Off. The pH feed output is activated based on a simple above or below setpoint decision. When the measured pH value is less than or equal to the pH setpoint (pH Feed: Acid selected) or greater than or equal to the pH setpoint (pH Feed: Base selected) the pH output feed is turned off. Otherwise, the pH feed output is turned on. On On (Default). The pH feed output is activated based on the difference between the pH setpoint and the measured pH value. As the difference increases, the duration the pH feed output is turned on increases to 20, 30, 40, and 50 seconds of the 60 second cycle, and then the pH feed output is turned on continuously. CONTENTS COPYRIGHT 2010 HAYWARD INDUSTRIES, INC. ALL RIGHTS RESERVED