Thermo Fisher Scientific Eutech 2700 Series - Manual (Page 49)

45
23.
Troubleshooting
Parameter Cause Solution
pH Won’t accept 1 st
calibration point
New calibrations must begin with
neutral standard (7.00 or 6.86)
pH Cal points are too
close
Custom pH buffer calibration values
must be at least 1.0 pH unit apart.
pH Reading is 7.00
and won’t change
Electrode tip may be cracked or
broken. Replace electrode.
pH or Ion Slope error /
Calibration error
Calibration values are too far apart, or
too far from ideal values. Check the
electrode, use fresh buffers, and check
meter settings. Electrode may require
filling solution, conditioning, or
complete replacement. Refer to
electrode manual.
Ion Display reads “- - -“ 2-point Ion calibration is required; no
calibration is stored in memory.
Conductivity Can’t adjust / can’t
calibrate
AUTO calibration values (84 µS, 1413
µS, 12.88 mS, or 111.8 mS) are not
used. Change Cal Method to MANUAL.
Conductivity 2 nd Calibration point
replaces the 1st
Only one point per range can be
calibrated. Re-consider your SINGLE or
MULTI Cal Points setting in Section 10.
TDS Standard does not
match
Adjust TDS factor as needed to correct
value. Refer to “Calculating TDS
Conversion Factor”.
DO Reading is very
slow to stabilize
Ensure stirrer motor is on during
solution measurement and temperature
is stable. If electrode is old, gold
cathode may be tarnished—buff with
disk or pencil eraser. Replace
membrane, electrolyte and recondition