Hanna Instruments HI 23 User Manual
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MAIN FEATURES OF DIFFERENT MODELS
• Display: large LCD with 4 ½ 13 mm digits and 3 ½ 7.7 mm
digits.
• LEDs: four LEDs are provided for signaling the energizing
of relays 1 and 2 (yellow LEDs) and alarm relay (a green
and a red LED).
• Relays: 2 output relays for low conductivity or high con-
ductivity dosage (COM, NO and NC contacts) and
1 output relay for alarm condition (COM, NO and NC
contacts).
PRELIMINARY EXAMINATION
Remove the instrument from the packing material and exam-
ine it carefully to make sure that no damage has occurred
during shipping. If there is any noticeable damage, notify
your Dealer or the nearest Hanna Customer Service Center
immediately.
Note
Save all packing materials until you are sure that the instru-
ment functions correctly. Any damaged or defective items
must be returned in their original packing materials together
with the supplied accessories.
GENERAL DESCRIPTION
HI 23 and HI 24 series are real time microprocessor-based
EC or TDS controllers. They provide accurate measurements,
flexible ON/OFF or proportional control capabilities, ana-
log input and output, dual setpoint and alarm signal.
The system is composed of a case inside which the signal
conversion circuitry, the microprocessor circuitry and the
output power drivers are contained.
GREAT FLEXIBILITY
The HI 23 and HI 24 controller series offer a great flexibility
with the possibility to connect a large variety of peripherals,
such as pumps, valves, relays and other control devices.
Each output can be fully programmed. The input can be
from a conductivity probe or from a 4-20mA transmitter. A
programmable analog output can be used for monitoring or
other purposes.
The controller also has the capability to communicate with a
computer via RS485 bus and to be part of an RS485 net-
work.
This allows the control of any process where conductivity is
involved.
The figure below illustrates the connection possibilities of ad-
vanced Hanna controllers, such as HI 23 or HI 24.