Hanna Instruments HI 9321 - Manual (Page 18)

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TROUBLESHOOTING GUIDE
Symptoms Problem Solution
The meter is slow in
responding or gives
faulty readings
The meter does not
accept the 2
nd buffer
solution for calibration
The reading drifts
Display shows:
Display shows:
Display shows:
Display shows:
"WRONG
BUF
1 "
and
"WRONG "
Display shows:
"WRONG
BUF
2
"
and
"WRONG "
The meter does not
work with the tem-
perature probe
The meter fails to cali-
brate or gives faulty
readings
The electrode is not
working or the reference
junction is clogged
Out of order pH elec-
trode
Defective pH electrode
Out of range pH scale
Out of range tempera-
ture scale
Out of range mV scale
Erroneous buffer solution
used for offset calibra-
tion
Defective electrode
Erroneous buffer solution
used for slope calibra-
tion
Defective electrode
Out of order temperature
probe
Out of order pH elec-
trode
Leave the electrode in a stor-
age solution after cleaning
the junction. If problem per-
sists, replace the electrode
Follow the cleaning proce-
dure. If this doesn't work
replace the electrode
Replace the electrode
a) Recalibrate
b) Make sure the pH
sample is in the 0 to 14
range
c) Check the electrolyte level
and the general state of
the pH electrode
Make sure the temperature
is in the 0 to 100°C range
and the temperature probe
is plugged in
Electrode not connected
Make sure the buffer setting
is correct and the solution is
fresh. Replace the buffer if
necessary
Replace the electrode
Make sure the buffer setting
is correct and the solution is
fresh. Replace the buffer if
necessary
Replace the electrode
Replace the probe
Replace the electrode