HI 9920

Industrial Grade ORP Controller with Proportional Dosage
HI 9920 is an ORP controller with a single set point for user selectable dosage of reducing or oxidizing solutions. Any ORP electrode ending in a BNC connector can be directly attached to the controller. With proportional control, you can fine tune your treatment plant and minimize the use of chemicals. The proportional setting can be adjusted through the time cycle from 0 to 90 seconds and the band from 0 to 200 mV. The set point can be accurately adjusted through coarse and fine trimmers. A pump or electrovalve can be wired directly to the controller and be powered through the terminal.

In addition to the set point relay, HI 9920 also provides for an alarm relay. The alarm is activated when the measurements exceed the operator adjustable threshold of 50 to 250 mV from set point. For extra security, a maximum dosing time from 1 to 10 minutes can also be set, after which the alarm is activated to signal an abnormality. The alarm configuration is alterable in a normally-closed or normally-open state to accommodate Fail Safe installations.

Any recorder accepting a 0-20 or 4-20 mA output can also be hooked up to the controller. Users can see the controller’s status, even from a distance, by observing the dosage or alarm LED’s. To speed up wiring, HI 9920 comes with extractable terminal modules. Once wired up, the compartment containing the connections is protected behind a fire-retardant ABS removable panel.

HI 9920 also provides for a matching pin/ground probe to eliminate interference and prolong the electrode’s life.

Specifications
Range  -500 to 1500 mV
Resolution  1 mV
Accuracy @ 20°C  ±5 mV
Calibration  through “CAL” trimmer
Setpoint  from -500 to 1500 mV with “COARSE” and “FINE” 2 trimmers with “OXID” or “RED” selection for oxidizing or reducing dosage
mA Output  user-selectable 0 to 20 mA or 4 to 20 mA over the -500 to 1500 mV range with isolated output
Proportional
Control  ORP setting is adjustable from 0 to 200 mV and time cycle from 0 to 90 seconds
Alarm Contact  normally open or normally closed isolated outputs (max. 2A, max. 240V, resistive load, 1,000,000 strokes). Terminals are activated when the ORP value varies by more than the user selectable interval (0 to 200mV) from set point, or due to overdosage
Dosing Terminals  relay terminals (115 to 240V, max.2A, 1,000,000 strokes) are activated when mV exceeds the set point with “RED” dosage or when mV falls below the set point with “OXID” selection
Power Supply  110/115 VAC or 220/240 VAC; 50/60 Hz
Environment  -10 to 50°C (14 to 122°F); RH max 95% non-condensing
Case Material  fiber-reinforced, self-extinguishing ABS
Dimensions  221 x 181 x 86 mm (8.7 x 7.1 x 3.4’’)
Weight  1.6 kg (3.5 lb.)

Accessories
Solutions
HI 7020L  ORP Test Solution at 200/275 mV (@20°C)
1 x 500 mL bottle
HI 7021L  ORP Test Solution at (240 mV @ 25°C/77°F)
1 x 500 mL bottle
HI 7022L  ORP Test Solution at 470 mV @ 25°C/77°F)
1 x 500 mL bottle
HI 7091L  Reducing Pretreatment Solution
1 x 500 mL bottle
HI 7092L  Oxidizing Pretreatment Solution
1 x 500 mL bottle
Accessories
HI 8427  pH and mV Precision Simulator
HI 931001  pH and mV Precision Simulator