7. Questions and Answers
28
7. Questions and Answers
Question
Possible causes
Possible solution
Readings instable.
Static charge.
Rinse off pH electrode
with tap water or
low
concentration
soap
water.
Air cushion from measurement
Shake pH electrode in a
electrode gets into measurement downward direction like
tip.
with a fever thermometer.
pH electrode has dried out.
Place pH electrode for
several hours in water or
diluted
hydrochloric
acid.
lights up.
Remaining capacity of battery
Change battery (See
< 10h.
6.4 Changing battery,
P.
11)
Instrument switches
Auto Off function is switched on. Auto Off.
itself off.
(See 5.2 Setting
instrument,
P.
8)
Er1
lights up.
Invalid gradient value
Recalibrate instrument,
of pH electrode.
a new buffer solution
could
be
used.
pH electrode defective.
Change probe.
Er2
lights up.
Invalid offset value
Recalibrate instrument,
of the pH electrode.
a new buffer solution
could
be
used.
pH electrode defective.
Change probe.
Er3
lights up.
Invalid gradient value
Recalibrate instrument,
of pH electrode following
a new buffer solution
3 point calibration.
could be used.
pH electrode defective.
Change probe.
Er4
lights up.
Probe not inserted correctly.
Check connection.
pH electrode defective.
Change probe.
If we have not answered your question, please contact your
nearest distributor or Testo Customer Service point. For contact
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service-contact
1.888.475.5235
www.
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