DeFelsko PosiTector SST Bedienungsanleitung Seite 8

Calibration, Verification, and Adjustment
Three steps ensure best accuracy...
1. Calibration: typically performed by the manufacturer. All probes
include a Certificate of Calibration.
2. Verification of Accuracy: typically performed by the user by
measuring known reference standards such as the supplied
conductivity standard.
3. Adjustment: to a known conductivity standard.
Calibration - Calibration is the high-level, controlled and documented
process of measuring traceable calibration standards over the full
operating range of the probe, and verifying that the results are within
the stated accuracy of the probe. Calibrations are performed by the
manufacturer, their authorized agent, or by an accredited calibration
laboratory in a controlled environment using a documented process.
Verification of Accuracy - Verification is an accuracy check performed
by the user with a solution of known conductivity. To perform a
verification, ensure that the conductivity standard and instrument are at
the same temperature. Remove any remaining DI water in the test cell
by filling it with the conductivity standard, then inverting the test cell to
empty it. Fill the test cell with the conductivity standard again. If the
reading is not within the combined tolerance of the gage and
conductivity standard, proceed to Cleaning the Test Cell, below.
Cleaning the Test Cell - If the Verification reading is outside the
combined accuracy of the conductivity standard and gage, the probe
may need to be cleaned by filling it with DI water and rubbing the walls
of the cell with a supplied foam tip swab. Rinse with DI water several
times before using the cell.
Verify accuracy at the beginning and the end of each work shift. During
the work shift, if the Gage is dropped or suspected of giving erroneous
readings, its accuracy should be re-verified.
Adjustment - Adjustment, or Calibration Adjustment, is the act of
aligning the Gage's readings to match that of a known conductivity
standard. (see Cal Adjust, pg. 9)
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