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ORP MEASUREMENTS (not for HI 98180)
To perform ORP measurements, connect an optional ORP electrode (see “Accessories“
section) to the instrument and turn it ON.
If necessary, enter the mV mode by pressing
RANGE
until the display changes to mV.
Submerge the ORP electrode tip (4cm/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 (see “Accessories” section, page 65).
RELATIVE mV MEASUREMENTS (not for HI 98180)
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 (HI 98184, HI 98185 only)
To perform ion concentration measurements, connect an optional ISE electrode
and the corresponding reference (if necessary) to the instrument and turn it
ON.
