Hanna Instruments HI 98150N - Manual (Page 10)

10
Submerse the ORP electrode tip (3cm/1¼”)
into the sample to be tested and wait a few
seconds for the reading to stabilize.
Measurements within the ±699.9 mV range
are displayed with 0.1 mV resolution, while
outside this range the resolution automatically
switches to 1 mV.
The “
ATC” (or “MTC”) tag is turned off because ORP measurements 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 41).
RELATIVE mV MEASUREMENTS (HI 98150 & HI 98160 only)
To enter Relative mV mode, press
2nd then
Mode while in mV measurement mode. The
relative mV reading will be displayed on the
primary LCD and the current temperature
value on the secondary LCD.
Relative mV is an operation mode in which the
displayed electrode potential (mV) can be
changed by means of a calibration control
offset. See page 17.
TEMPERATURE MEASUREMENTS
The pH electrodes used for
HI 98140 and HI 98150 also
include an integral temperature measuring element.
For
HI 98160 connect the HI 7662 temperature probe to
the appropriate socket, submerse the temperature probe
into the sample and permit it to equilibrate by watching
the reading on the secondary LCD.
If the temperature is out of range, or the temperature probe is not
connected (
HI 98160 only) the instruments will display the last in
range temperature reading and enter MTC mode (see page 9).
Note: The temperature can be displayed in Celsius degrees (ºC) or in
Fahrenheit degrees (ºF) (see SETUP for details, page 21).
BACKLIGHT FEATURE
The instrument is provided with a Backlight feature to
enhance display readability in low light conditions. It
can be easily toggled on and off through the keypad by
pressing
Light.
Note: The backlight automatically shuts off after a set time period to
save battery life (see SETUP for details, page 21).
If battery percentage is less than 20% the backlight can not be ON.