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ORP MEASUREMENTS
To perform ORP measurements, connect an optional ORP electrode to the instrument and turn it ON.
Press
RANGE
key until mV range is displayed, if necessary.
Submerge the ORP electrode tip (4 cm/1½”) into the sample to be tested and wait a
few seconds for the reading to stabilize.
Measurements are displayed with 0.1 mV resolution.
The
“ATC”
(or
“MTC”
) message is turned off because mV readings are not temperature
compensated.
For accurate ORP measurements, the surface of the electrode must be clean and smooth.
Pretreatment solutions are available to condition the electrode and improve its response time.
RELATIVE mV MEASUREMENTS
To enter Relative mV mode, press
MODE
while in mV measurement mode. The relative mV reading
will be displayed along with the Absolute mV value and the current temperature readings.
The relative mV reading is equal to the difference between the absolute mV input value and relative
mV offset established in the relative mV calibration.
Note: If using the pH electrode while in mV mode, the instrument will measure the mV
generated by the pH electrode.
ISE MEASUREMENTS (HI98191 only)
To perform ion concentration measurements, connect an optional ISE electrode and
the corresponding reference (if necessary) to the instrument and turn it ON.
Enter the ISE mode by pressing
RANGE
until the display changes to ISE range.
Submerge th e ISE electrode tip (4 cm/1½”) into the sample to be tested and wait a
few seconds for the reading to stabilize.
OPERA
TIONAL GUIDE