Hanna Industrial Grade EC Controller with Proportional Fertilizer Dosing for Hydroponics Applications, 230V - HI9931-2

HI9931-2 Industrial Grade EC Controller with Proportional Fertilizer Dosing for Hydroponics Applications, 230V by Hanna Instruments

HI 9931 is a wall mounted meter that measures and controls conductivity in the 0 to 10 mS/cm range. A single set point allows for proportional dosage of fertilizer solutions. 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 mS/cm. Calibration and set points have a coarse and fine tuning trimmers. A pump or electrovalve can be wired directly to the controller and be powered through the terminals.

HI 9931 also provides for an alarm relay which is activated when the measurements exceed the set point by a user selectable margin from 0.5 to 2.5 mS/cm. The alarm also triggers 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. HI 9931 also provides an isolated output signal which is user selectable between 0-20 or 4-20 mA.

HANNA four-ring conductivity probes ending in a DIN connector can be quickly attached to the HI 9931. Readings are automatically compensated for the effects of temperature in the 0 to 50°C (32 to 122°F) range. For quick and easy wiring, HI 9931 comes with extractable terminal modules. Several LED's show whether the set point or alarm relays have been activated.

Order Information:

HI 9931 is supplied complete with instructions.