Troubleshooting - LaMotte pHPLUS DIRECT 2 Manual

6. TROUBLESHOOTING

Problem
No display
"---" on
display
"LO" displays
in the
DISPLAY
Unstable
reading
"Er1" display
"Er2" display
"Er3" display
"Er4" display
Not able to
calibrate
Cause
Batteries not in place.
Meter does not have 2
point calibration
Low battery
a) Electrode not deep
enough in sample
b) Dirty electrode.
c) Broken electrode
Buff er value out of
tolerance
Single point calibration
ISE slope not within the
specifi ed tolerance
Calibration points not
within 1 decade
a) Display freezes
b) Faulty electrode
c) Inaccurate buff er
Solution
a) Insert batteries.
b) Re-insert batteries in
correct polarity.
Perform 2 or 3 point ion
calibration.
Replace batteries.
a) Place electrode deeper
in sample.
b) Clean electrode and
recalibrate.
c) Replace electrode.
Use fresh pH buff er
solution and recalibrate.
Ensure correct pH buff er
group was selected.
Perform at least 2 point
calibration.
Check ISE is in good
working condition-refer to
ISE section of manual.
Ensure calibration points
are within 1 decade of
each other.
a) Release reading by
pressing HOLD.
b) Replace electrode.
c) Replace expired buff er
solutions.
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