Endress+Hauser CA76NA, Руководство по эксплуатации

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CA76NA Operation
Hauser 39
Parameters
Function Options Info
Measurement Sequence Calibration interval
• Disabled
• 4 h
• 12 h
• 24 h
• 48 h
• 72 h
• 120 h
• 168 h
Reg.:
Number of regenerations
• 6 h
• 12 h
• 24 h
Measuring time
• Disabled
• 15 min
• 20 min
• 30 min
• 60 min
• 90 min
• 2 h
Make the following settings:
• The intervals at which the analyzer starts an
automatic calibration
• How long the analyzer measures the sodium
concentration in the particular channel
• The number of regenerations to be performed
in the calibration interval

It is not possible to guarantee the accuracy
according to the specifications with a
measuring time of 15 or 20 min. This is
particularly true if channels with very
different concentrations of sodium ions are
measured in direct succession.
Regenerations are performed automatically at
equal intervals within the calibration interval.
For example, if the time interval for the
calibration is set to 48 hours and the number of
regenerations is set to 3, a regeneration is
performed 12 hours, 24 hours and 36 hours
after the calibration, before a new calibration
begins again after 48 hours.
The regeneration is needed to maintain the
functional integrity of the sodium electrode
when operating in water that is low in sodium.
In contrast to calibrations, the regeneration
process requires significantly less time, thereby
minimizing the time when the analyzer is not
available for measurements.
If the operating mode is set from OFF to
AUTOMATIC , the device begins analyzing in
succession - for the specified time - all the
channels which have been assigned a measuring
time. The time until the end of the current
analysis of the channel displayed is shown on
the bottom row of the measured value display.
Once the time has elapsed (0 min on the
measured value display), the device starts
analyzing the channel again.
pH-Control
pH set point The set point for pH regulation can be changed
depending on the accuracy requirements of the
Na concentration measurement and the desired
Na measuring range
A set point of pH=11.00 is generally
recommended.
pH lower limit The lower limit value ensures that the pH value
does not stray too much from the set point
during the regulation. If the lower limit value is
undershot for more than 10 minutes, the device
switches to the
Off state and stops the
measurement. If this happens, the pH too small!
error is displayed. If the set point has been set to
pH=11, a value of 10.80 is recommended for the
lower limit value.
If a lower pH value is set, lower the limit further,
while making sure to keep a ∆pH of at least 0.2.
Alarm delay Alarm delay if value is under range
Standard 600 s