Metrohm 900 Touch Control Manual - Manual (Page 178)

15.7 Custom electrode type
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900 Touch Control
Upper limit Uoff
Upper limit value for the offset voltage, i.e. the voltage at pH = 7.0. The
value applies for all ratings.
Input range –999 - 999 mV
Default value 15 mV
15.7.1 Limit values for the electrode rating
You can define limit values for the three electrode ratings Excellent elec-
trode, Good electrode and Usable electrode. These values represent
maximum values that may not be exceeded (exception: Min. slope =
minimum value).
Streaming potential
The streaming potential is the difference between the measured voltages
in stirred and unstirred solution.
for very good electrodes:
Input range
–999.9 - 999.9 mV
Default value 2.5 mV
for good electrodes:
Input range
–999.9 - 999.9 mV
Default value 3.0 mV
for usable electrodes:
Input range
–999.9 - 999.9 mV
Default value 4.0 mV
Drift
The drift in stirred solution is determined for each buffer. The sum of these
values is compared with this value here.
for very good electrodes:
Input range
0.1 - 9.9 mV/min
Default value 2.0 mV/min
for good electrodes:
Input range
0.1 - 9.9 mV/min
Default value 2.5 mV/min
for usable electrodes:
Input range
0.1 - 9.9 mV/min
Default value 3.0 mV/min