Hanna Instruments HI 9023C, Instruction Manual

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ON/OFF
ON/OFF
°C
°C
or
INITIAL PREPARATION
Each meter is supplied complete with batteries.
Remove the back cover, unwrap the batteries and
install them while paying attention to polarity.
HI 9023C, HI 9024C, HI 9025C:
To prepare the instrument for use connect the pH electrode and the
temperature probe to the BNC and temperature sockets on the top of
the instrument. The temperature probe can be used independently to
take temperature measurements, or it can be used in conjunction with
the pH electrode to utilize the meter's ATC capability. If the probe is
disconnected, temperature can also be set
manually with the UP and DOWN keys. To
switch the instrument on, press and hold the
ON/OFF key for a fraction of a second. The
meter has a built-in protection against electro-
magnetic interference and the delayed response
of the keys assures that the commands are not
mistaken for stray signals.
HI 9110 and HI 9210:
Connect the pH electrode to the BNC connector on the top of the
instrument and press the ON/OFF key.
HI 9210N and HI 9023CN:
Connect the pH/°C electrode to the DIN connector on the top of the
instrument and press the ON/OFF key.
OPERATIONAL GUIDE OPERATIONAL GUIDE OPERATIONAL GUIDE OPERATIONAL GUIDE OPERATIONAL GUIDE
ON/OFF
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TAKING REDOX MEASUREMENTS
(HI 9023C & HI 9025C only)
HI 9023C and HI 9025C have the capability to take ORP measure-
ments. An optional ORP electrode must be used to perform these
measurements.
Oxidation-Reduction Potential (REDOX) measurements provide the quan-
tification of the oxidizing or reducing power of the sample tested.
To correctly perform a redox measurement, the surface of the ORP
electrode must be clean and smooth.
In order to improve performance and obtain a faster response time,
precondition your ORP electrode with reducing or oxidizing solutions.
Generally speaking, if the ORP mV reading corresponding to the pH
value of the solution is higher than the values in the table below, an
oxidizing pretreatment is necessary; otherwise a reducing pretreatment
is necessary:
pH mV pH mV pH mV pH mV pH mV
0 990 1 920 2 860 3 800 4 740
5 680 6 640 7 580 8 520 9 460
10 400 11 340 12 280 13 220 14 160
Reducing pretreatment: immerse the electrode for a few minutes in
HI 7091 .
Oxidizing pretreatment: immerse the electrode for a few minutes in
HI 7092 .
When not in use, the tip of the electrode should be kept moist and
safe from any mechanical stress which might cause damage to the
glass/platinum junction.