pH Controller
The HI 9910 is a pH controller with a single set point for proportional dosage. The proportional control can be fine tuned through two dials on the font panel. The time cycle is adjustable from 0 to 90 seconds and the proportional band from 0.0 to 2.0 pH. Course and fine as well as offset and slope trimmers make accurate setting and calibration easy and convenient. The pump can be wired directly to the controller and powered through the terminals. The HI 9910 also provides an alarm. The alarm is activated when the measurements stray away from the set point by a predetermined value in the 0 to 2 pH range. A max. dosing time from 1 to 10 minutes can be set, after which the alarm is activated to warm of an abnormality. A dial on the front panel renders manual temperature compensation fast and easy. The HI 9910 comes with extractable terminal modules. Once wired up, the compartment containing the connections is protected behind a fire-retardant and waterproof ABS panel. Several LED’s and an external red light show whether the set point or alarm relays have been activated. For use with OP1, OP3 and OW1.

Conductivity Controller
HI 9931 is a conductivity wall-mounting meter that measures and controls conductivity in the 0 to 10 EC (mS/cm or mmho/cm). A single set point allows for proportional dosage. The proportional settings can be fine tuned through two conveniently positioned dials on the front panel. The time cycle is adjustable from 0 to 90 seconds and the proportional band from 0 to 1.6 EC. Course, fine and slope trimmers make accurate setting and calibration easy and convenient. The pump can be wired directly to the controller and be powered though the terminals. HI 9931 also provides for an alarm relay which is activated when the measurements exceed the se tpoint by a user-selectable margin from 0 to 2.0 EC. The alarm also goes off if due to a malfunction, the continuous dosing time exceeds the operator adjustable period of 1 to 10 minutes. The alarm can be configured in either normally closed or open position and turned off during maintenance. A four ring conductivity probe is attached to the controller for accurate measurement. Temperature is automatically compensated for in the 0 to 50°C (32 to 122°F) range. Several LED’s and an external red light show whether the set point or alarm relays have been activated. For use with SP1 and SPR2.

Diaphragm Pump
A diaphragm pump with variable output control for use with the pH and conductivity control units.