Calibration; Calibration Check; Calibration Adjustment - GE Druck DPI 610 IS User Manual

Calibration

General
The instrument is supplied by the manufacturer, complete with calibration
certificate(s). A re-calibration interval of 12 months is recommended. The actual
re-calibration interval will depend upon the total measurement uncertainty which
is acceptable for a particular application.
The DPI 615 are very precise measuring instruments and the test equipment and
conditions of test must be suitable for the type of work. The use of a Class A
compensated deadweight tester is essential. The tests should be carried out in a
controlled environment by a calibration technician*.
If, when the accuracy of the instrument is checked, it is found to fall outside the
specification, calibration adjustment can be undertaken to compensate errors.
The manufacturer offers a comprehensive and, if required, NAMAS accredited
calibration service.
* A calibration technician must have the necessary technical knowledge,
documentation, special test equipment and tools to carry out the calibration
on this equipment.

Calibration Check

At the chosen interval, the instrument readings should be compared with a known
standard. Any deviations between the instrument and the standard should be
noted, taking due account of the traceability (accuracy to a National Standard). If
these deviations exceed the published tolerance, or any other suitable chosen
performance standard, then the user may wish to carry out a calibration
adjustment .
It is recommended that measurements be checked at 0, 20, 40, 60, 80 and 100% of
full-scale on an ascending and descending run.

Calibration Adjustment

If the instrument is operating correctly, only zero and full-scale calibration will
vary. Any excessive non-linearity or temperature effects indicate a fault . The
instrument should be returned to a qualified service agent.
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