Sartorius PT-10 Mode D'emploi page 21

Electrode Test
pH=7 0 ± 30 mV
pH=4 159 to 186 mV
higher than pH 7
pH=10 159 to 186 mV
lower than pH 7
Troubleshooting
1. If "- - - - -" is displayed, the signal from the electrode
is out of range.
This might indicate that the electrode is not in the
solution.
2. If "Error" is displayed with the "Slope" symbol,
this indicates an error in the electrode reaction.
If this is displayed during standardization, this means
the electrode shows under 90% or over 105% of the
correct slope.
The "Error" message can mean one of the following:
– bad electrode
– bad buffer(s)
– wrong buffer selected
3. If "- - -" is displayed, the meter has detected an error
in the ATC probe.
This indicates that no ATC probe is used for tempera-
ture compensation (default temperature: 25°C).
4. Testing a pH-electrode:
Immerse the electrode in a good pH 7 buffer.
Press the [Mode] key to activate mV mode and record
the displayed value. Make sure the meter is in mV mode
and not in relative mV mode. Repeat the same steps
with a pH 4 or pH 10 buffer. At a temperature of
approximately 25°C, the electrode signal should be
within the limits shown here.
21