Hach Ultra ORBISPHERE 511 Quick Manual page 11

Calibration Results
A calibration screen will be displayed showing
current measurement data which is continually
refreshed.
The value "% ideal slope" is a percentage of the
slope against the ideal slope. If this percentage is
not within the accepted range, an error message
is displayed and the calibration process fails. A
warning message will be displayed when this
value is close to the boundaries, but when
calibration can be accepted.
The message is first displayed in the result box.
The dialog box with the error message or the
warning is displayed when the finish button is
pressed.
The value "% last calibration" shows the ratio
between the current measurement and the
previous sensor calibration.
The value "% variation" indicates the variation
during the last 3 measurements, which is the
stability of the measurements. A variation as low
as possible is needed for a precise calibration.
T he display sho ws t he actua l calib ra tio n
p a r a m e t e r s , a n d t h e a c t u a l r e a d i n g s
(temperature, barometer, slope).
In case of a calibration failure, consider replacing
the membrane. See the TC Sensor Maintenance
Manual for details.
Calibration (cont)
Verification
Similar to the calibration procedure, but for
verification of the actual calibration values. The
result of the measurements made during the
verification is not stored and the actual calibration
data is not modified.
Calibration Errors (EC and TC sensors)
Calibration is not possible:
•
•
•
When "ratio ideal current" is greater than
170% or smaller than 30%
When sensor cannot measure
When "ratio ideal current" is greater than
150% or smaller than 50%, a warning is
displayed but calibration is valid
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