Hanna Instruments HI 9914 - Manual (Page 3)

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MECHANICAL LAYOUT
Front view
The molded mounting holes in the 4 corners provide for quick and secure
installation. No additional tool is needed. All the electrical connections
and control are located on the front panels so that adjustments can be
made without removing the unit.
Bottom view
The modular design isolates the control circuitry from the contacts, mak-
ing possible to wire the connections and then close the compartment.
Adjustments can be made through the “control area” (left panel),
without open the connection compartment (right panel).
tivity of the irrigation water, while the pH regulator can be set for high
or low pH correction.
For a better result, the conductivity and pH controls are time separated
and a timed operation mode avoids overdosing of fertilizer or acid.
The controller is designed with relay outputs for pH and conductivity
control (2A/240V), each one corresponding to a status LED for visual
check.
Three level sensors are used to offer the best control of water level, alarm
conditions and irrigation sequences.
The beginning of the irrigation can be triggered through an external
signal, while an additional input allows to restart the cycle at any time.
The good water composition is signaled on the front panel and with an
external signal for remote operating purposes.
The controller is equipped with an alarm system 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 2A (240 V) relays.
Two models are available, with different power supply input:
• HI 9914-1 works with 110/115 Vac input
• HI 9914-2 works with 220/240 Vac input