AMI INSPECTOR Conductivity
Maintenance
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6.4.
Quality Assurance of the Instrument
Every SWAN on-line instrument is equipped with integrated, auton-
omous quality assurance functions to survey the plausibility of each
measurement.
For AMI Powercon Specific and AMI Powercon Acid these are:
continuous monitoring of sample flow
continuous monitoring of the temperature inside the transmit-
ter case
periodic accuracy test with ultra high precision resistors
Further a manual, menu driven inspection procedure can be carried
out using a certified reference instrument. Running at the same
sampling point as an inspection equipment, the AMI Inspector Con-
ductivity, verifies the measuring results. After enabling the quality
assurance procedure, by defining the quality assurance level, the
instrument reminds the user periodically to run the procedure and
results are stored in a history for review.
Quality
assurance
level
Central feature of the quality assurance function is the assignment
of the monitored process to a Quality assurance level.
There are three predefined levels plus a user level. Hereby the in-
spection interval, the deviation limits of temperature and measuring
result between the inspection equipment and the monitoring instru-
ment are defined.
Level 1:
Trend;
Measurement used as an additional informa-
tion to follow the process indicating trends.
Level 2:
Standard;
Monitoring of conductivity. In case of in-
strument failure, other parameters can be used for process
monitoring.
Level 3:
Crucial;
Monitoring of critical processes, value is
used for control of another part or subsystem (valve, dosing
unit, etc.).
Additional level:
Quality level 4:
User;
User defined inspection interval, maxi-
mal deviation of temperature and measuring result.
