TPS Aqua-pH, Manual, Page: 20 / 27

Page 19
pH and mV Troubleshooting, continued...
Unstable
readings. 1. Reference junction
blocked.
2. Glass bulb not clean.
3. Bubble in glass bulb.
4. Faulty connection to
meter.
5. Reference junction not
immersed.
6. KCl crystals around
reference junction, inside
the electrolyte chamber.
Clean reference junction, as
per instructions supplied
with the sensor.
Clean glass bulb as per
instructions supplied with
the sensor.
Flick the sensor to remove
bubble.
Check connectors. Replace
if necessary.
Ensure that the bulb AND
the reference junction are
fully immersed.
Rinse electrolyte chamber
with warm distilled water
until dissolved. Replace
electrolyte.
Inaccurate
readings, even
when calibration
is successful. Reference junction blocked. Clean reference junction, as
per instructions supplied
with the sensor.
Displays 7.00 for
all solutions. Electrical short in connector. 1. Check connector.
Replace if necessary.
2. Replace sensor.
Displays 4-5 pH
for all solutions. Glass bulb or internal stem
cracked. Replace sensor.
9.3 Temperature Troubleshooting
Symptom Possible Causes Remedy
Displays “ OVR
o
C ”
when sensor is
plugged in.
1. Faulty sensor.
2. Faulty instrument.
Fit new sensor, part number
121247.
Return instrument to factory
for repair.
Temperature
inaccurate and
cannot be
calibrated. 1. Faulty connector.
2. Faulty sensor.
3. Faulty instrument.
Check the connector and
replace if necessary.
Fit new sensor, part number
121247.
Return instrument to factory
for repair.