pH Controller

The model 2200P pH controller features dual relays with adjustable on/off cycling action that enables the system to avoid overshoot. This microprocessor-based controller incorporates dual 5 amp independent relays individually programmable for true bi-directional control. Relay A has an additional attribute to avoid overshooting. The adjustable On/Off timer produces a "cycling action" allowing time for chemical additives to completely mix before readings are re-taken. Independent adjustment of the On time and Off time are accomplished using a display driven menu. A third alarm relay with fixed deadband provides high and low alarm. This alarm can be programmed to energize in response to a system malfunction, lighting a LED on the front panel.

It uses a step through menu printed on the front panel and reserves the large ½-in. LED display for readings. The main processor functions are programmed using a "call function" menu. The functions are printed directly on the front panel. The list of functions include: password, test, calibration, auto cal, temperature, status, output high, output low, cycle A on/off, cycle B on/off. In addition, the dual independent relays and alarm relay are programmable in the same fashion. This setup allows programming of setpoints and deadband for the relays as well as high and low output for the alarm relay. An Auto/Off/On switch allows the user to override the action of Relay A.

When the system is used with the company's differential pH probe with integral temperature sensor, temperature readings can be displayed as well as a 0-5 Vdc analog output may be selected to follow either pH or temperature.

AquaMetrix, Inc., 4-30 Royal Crest Court, Markham ON, Canada, L3R 9W8; phone: 905-946-1064; fax: 905-946-8064