DeFelsko PosiTector 200 v.1.2 - Manual (Page 13)

Page 13
Calibration, V Calibration, V erification and erification and Adjustment Adjustment
Three steps ensure best accuracy…
1. Calibration - typically done by the manufacturer or a qualified lab
2. Verification of Accuracy - as done by the user
3. Adjustment - to a known thickness
Calibration
Calibration is the controlled and documented process of measuring traceable
calibration standards and verifying that the results are within the stated accuracy of
the Gage. Calibrations are typically performed by the Gage manufacturer or by a
certified calibration laboratory in a controlled environment using a documented
process. The standards used in the calibration are such that the combined
uncertainties of the resultant measurement are less than the stated accuracy of the
Gage. Typically a 4:1 ratio between the accuracy of the standard and the accuracy
of the Gage is sufficient.
The PosiTector 200 is shipped with a Certificate of Calibration showing traceability
to a national standard. For organizations with re-certification requirements, the
PosiTector 200 may be returned at regular intervals for calibration. DeFelsko
recommends that our customers establish the gage calibration intervals based
upon their own experience and work environment. Based on our product
knowledge, data and customer feedback, a one year calibration interval from either
the date of calibration, date of purchase, or date of receipt is a typical starting point.
Verification
Verification is an accuracy check performed by the user using known reference
standards. A successful verification requires the Gage to read within the combined
accuracy of the Gage and the reference standards.
A reference standard is a sample of a known
thickness(es) against which a user may verify the
accuracy of the gage. Reference standards may
be coated thickness standards (pg.12), the
included plastic shims (pg.12), or sample parts
whose coating thickness has been determined
using other means.
To guard against measuring with an improperly adjusted Gage, verify the Gage at
the beginning and the end of each work shift.