JUMO AQUIS touch S, Assembly Instructions Manual

Page: 50 / 150

11 Calibration in general
50
• You must be logged in as a user with the right to perform calibrations. Fac-
tory-preset users have all of these rights.
⇨
"Passwords and user rights", page 77
• You must ensure that the calibration default settings for the individual analy-
sis inputs and, possibly, the universal inputs are set correctly. The explana-
tions of the calibration default settings can be found in the chapters on
calibration of the various analysis sensors.
• In the case of Ci analysis inputs, it should be noted that the optional boards
must undergo a basic calibration during the initial commissioning. If this has
not yet been performed, it is necessary to do so prior to any other calibration.
⇨
Chapter 9.3 "Ci base calibration", page 121
Manual entry of calibration values
If calibration values are known, they can also be entered manually. This may be
the case with temperature-compensated conductivity measurements, for in-
stance, when the temperature coefficient of a liquid is known. Another important
application case is the manual entry of relative cell constants of conductivity
sensors. If an ASTM test certificate showing precisely-measured cell constants
is available, in addition to entering the nominal cell constants in the configuration
of the conductivity sensor concerned (cf. Chapter 10.6.6 "CR/Ci analysis inputs
(conductive/inductive conductivity)", page 23), the relative cell constants of all
measuring ranges in the calibration values must be manually entered. The rela-
tive cell constants must be calculated from nominal cell constants (nameplate
for the sensor) and measured cell constants (ASTM test certificate):
(measured cell constant × 100 %) ÷ nominal cell constant = relative cell con-
stant.
Calculation example:
nominal cell constant = 0.1 cm-1
measured cell constant = 0.1014 cm
-1
rel. cell constant =
(0.1014 cm
-1
× 100 %) ÷ 0.1 cm
-1
= 101.4 %
Known calibration values are entered manually under:
Device menu > Calibration > Select Analog Input > Calibration Values
NOTE!
Incorrectly entered calibration values result in incorrect measured values.
Correct measurements are essential for control systems and limit
monitoring.