Microphone User Manual

24
Possible Solutions:
Replace the probe.
Replace the electrode and
repeat the pH calibration.
Leave the electrode in a
storage solution after clean-
ing the diaphragm.
If the problem is not solved,
replace the electrode and re-
calibrate the pH scale.
Try the cleaning procedure.
If this does not work, re-
place the electrode and
re-calibrate the pH. Use fresh
buffer solution.
Thermal equilibrium not
reached. Wait longer.
a) Verify the pH electrode is con-
nected.
b) Make sure the pH sample is
included between 0 and 14 pH.
c) Check the level of the electrode's
filling electrolyte and the state of
the electrode itself.
Verify the temperature probe
is connected and make sure
the °C is within -10/125°C
for HI8417 or -10/100°C for
HI8520/HI8521.
Verify the temperature probe
is connected and make sure
the mV is within ±1999
range.
Make sure that the buffer
solution used is of pH 7
and replace if necessary.
Replace the electrode and
re-calibrate the pH scale.
Be sure the correct pH buffer
solution is being used for
slope calibration (4.01,
9.18 or 10.01 pH).
Check the electrode and re-
place if necessary.
Symptoms are:
The instrument does
not work with the
HI7669/2W probe
(not HI8519)
The meter fails to
calibrate or gives
erroneous results
The meter is slow in
responding or gives
erroneous readouts
The meter does not
accept the 2nd buffer
solution
The reading drifts
"Err1" (for HI8417)
"E 1" (for HI8520/
HI8521) on the
display
"Err3" (for HI8417)
"E 2" (for HI8520/
HI8521) on the
display
"Err2" (for HI8417)
"E 3" (for HI8521)
on the display
"Err4" (for HI8417)
"E 4" (for HI8520/
HI8521) on the
display
"Err5" (for HI8417)
"E 5" (for HI8520/
HI8521) on the
display
TROUBLESHOOTING
The Problem is:
A defective ATC Probe
A defective pH electrode
The electrode is not
working or the dia-
phragm is clogged
A defective pH electrode
or bad buffer solution
Temperature not stable
Out of range on the pH
scale
Out of range in °C
Out of range in mV
Erroneous buffer solution
used for offset calibration
Defective electrode
Erroneous buffer solution
used for slope calibra-
tion
Defective electrode