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IM 12B03D02-01E
8-3
8
.
ORP Meter
(2) Rinse off the remaining sample solution, if any, from the electrode with water and
then wipe off water drops.
(3) Immerse the electrode tip in the check solution and wait until the reading has
stabilized. This should take 5 to 10 minutes.
(4) Read the mV value and solution temperature. The mV reading at the solution
temperature must be within the tolerance (640 mV) shown in Figure 8.2. If it falls
within the tolerance, the sensor is normal. If not, clean the sensor following the
procedure in Section 8.2.
400
300
200
100
0
0
10
20
30
40
50
Temperature (°C)
Oxidation-reduction potential (mV)
Quinhydrone solution
Tolerance
F0802.ai
Figure 8.2 Oxidation-Reduction Potential of Check Solution