10
RELATIVE mV MEASUREMENTS (HI 111 and HI 113)
Press
RANGE
until rEL message will be displayed on the secondary LCD line
for about one second and mV tag will blink. After one second the
temperature will be displayed on the secondary LCD.
The reading displayed by the instrument is equal to the difference between
the current mV input value and relative mV offset established in the relative
mV calibration.
TEMPERATURE MEASUREMENTS
Connect the
HI 7669/2W
temperature probe to the appropriate
socket and turn the instrument on.
Immerse the temperature
probe
into the sample and allow
the reading on the secondary LCD to stabilize.
MEMORY FUNCTION
Press and hold down
MEM
. The last reading will appear
on the LCD along with MEM tag until
MEM
is released.
Press
MR
and the previously memorized reading will be
displayed on the LCD with MEM tag.
pH CALIBRATION
Calibrate the instrument frequently, especially if high accuracy is required.
The instrument should be recalibrated:
Whenever the pH electrode is replaced.
At least once a week.
After testing aggressive chemicals.
If CAL INTV tags are blinking during measurement.
Every time you calibrate the instrument use fresh buffers and perform an
electrode Cleaning Procedure (see page 30).
MR
mV
MEM
pH
MEM
