อุปกรณ์วัด Control System (Industrial Grade Fertigation Controller for Process Control Requirements)

HI 9914

Industrial Grade Fertigation Controller for Process Control Requirements

HI 9914 is a wall mounted fertigation controller, designed to meet specific process control requirements in agricultural, horticultural and hydroponics applications. The controller is provided with two measuring channels, one for pH and one for conductivity. The readings are displayed simultaneously on two backlit, independent LCDs.

The conductivity probe is designed with a built-in temperature sensor which allows the controller to automatically compensate for the temperature effect. The differential input and the use of a matching pin prevent grounding problems and thus ensure longer life to the pH electrode.

The controller includes two regulators for pH and conductivity, that can be adjusted from the front panel by setting two independent thresholds. The conductivity and pH controls are time separated and have a timed operation mode to avoid overdosing of fertilizer or acid. The controller status is indicated by LEDs on the front panel. Moreover, the equipment is provided with a three-level sensor, to control the water level in mixing tanks, the alarm condition and irrigation sequences.

The instrument also features an alarm system, which is activated when an unusual working condition occurs. A humidity detector can be used to stop the controller if any leakage is detected. Water nozzle, circulation pump, feeding pump and alarm are equipped with relays.

Specifications

Range EC 0.00 to 10.00 mS/cm
pH 0.00 to 14.00 pH
Resolution EC 0.01 mS/cm
pH 0.01 pH
Accuracy @ 20°C EC ±5% f.s.
pH ±0.02 pH
Calibration EC manual, 1 point with slope trimmer (80 to 120%) on the front panel
pH manual, 2 point, with offset (±2 pH) and slope (80 to 120%) trimmers
Setpoint EC adjustable, from 0.50 to 10.00 mS/cm
pH adjustable, from 0.5 to 14.0 pH
Temperature
Compensation (EC)  automatic from 0 to 50°C
Analog Output  0-5V±5% (0.5V/mS); 0-7 V±5%?(0.5 V/pH)
Controller Output EC 2A, 220V relay
pH 2A, 220V relay
Timer  adjustable, from 1 to 10 minutes within a 15-minutes-time frame
Feed OK Output  12V, 15 mA current source
Humidity Sensor  activated if resistivity is below 220Ω
Water Nozzle Output  2A, 220V relay
Circulation Pump Output  2A, 220V relay
Feeding Pump Output  2A, 220V relay
Alarm Output  2A, 220V relay
Water Level Inputs  contact type water level sensors
User Input  contact type switch
External FILL Button  contact type push-button
Power Supply  ±10% 115 VAC or 230 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 90 mm (8.7 x 7.1 x 3.5’’)
Weight  1.75 kg (3.9 lb.)

Accessories

Solutions
HI 7004L  4.01 pH Buffer Solution
1 x 500 mL bottle
HI 7007L  7.01 pH Buffer Solution
1 x 500 mL bottle
HI 7010L  10.01 pH Buffer Solution
1 x 500 mL bottle
HI 7031L  1413 µS/cm EC Solution, 500 mL Bottle
HI 7039L  5000 µS/cm EC Solution, 500 mL Bottle
Probes
HI 3001D  Flow-thru Conductivity Probe with DIN Connection and 3 m cable