2402 pH Stratos® - Knick Elektronische Meßgeräte GmbH & Co.

ORP calibration
ORP calibration mode is automatically preset when ORP measurement
is configured. The potential of a redox electrode can
be calibrated using a redox buffer solution. For this purpose,
the difference between the potential measured and the potential
specified for the calibration solution is determined. During
measurement, the Stratos then adds this difference to the
potential measured.
mV ORP =mV meas + ∆mV
mV ORP =
mV meas =
∆mV =
displayed ORP
direct electrode potential
delta value, calculated during
calibration
It is also possible to relate the elctrode potential to another reference
system – such as the standard hydrogen electrode. In
that case, the temperature-corrected potential (see table) of
the reference electrode used must be entered. During measurement,
this value is then added to the ORP measured.
Please make sure that measurement and calibration temperature
are the same, since the temperature response of the reference
electrode is not automatically taken into account.
Temperature dependence of commonly used reference systems
Temperature
[°C]
Ag/AgCl/KCl
1 mol/l
[∆mV]
Ag/AgCl/KCl
3 mol/l
[∆mV]
Thalamid
[∆mV]
Mercury
sulfate
[∆mV]
0
10
20
25
30
40
50
60
70
80
249
244
240
236
233
227
221
214
207
200
224
217
211
207
203
196
188
180
172
163
-559
-564
-569
-571
-574
-580
-585
-592
-598
-605
672
664
655
651
647
639
631
623
613
603
88 Stratos e 2402 pH