Calibration – Hach-Lange SI792 P, SI792x P, SI792x P-FF, SI792x P-PA User Manual User Manual
Page 78
Calibration
76
Be sure that ORP is selected in the Configure, Output menu
(
Be sure that the measurement and calibration temperature are the
same. The temperature behavior of the reference probe is not
automatically taken into account.
Complete the following steps to calibrate the ORP probe:
1. Press
CAL
, enter passcode: 1100,
ENTER
. The display will show the
mV screen to be edited.
2. Remove the ORP and temperature probes from the process. Clean
the probes and immerse in the redox standard. Briefly stir the
solution with the probes.
3. Enter the millivolt value of the redox standard solution.
4. Press
ENTER
. The display will show the delta mV value.
5. Press
ENTER
. The display will show the measured mV value
alternating with Hold.
6. Press
ENTER
to return to the measurement mode.
7. Remove the probes from the solution, rinse and return to the
process. The HOLD mode will remain active for 20 seconds.
70
207
172
–598
613
80
200
163
–605
603
Table 20 Temperature-corrected potential of
commonly used reference systems (Continued)
Temperature
(°C)
Ag/AgCl/KCl
1 mol/L
(
Δ
mV)
Ag/AgCl/KCl
3 mol/L
(
Δ
mV)
Thalamid
(
Δ
mV)
Mercuric
sulfate
(
Δ
mV)