8
3.5 Verification of Calibration
All tension meters are calibrated with standard materials - such as polyamide monofila-
ment (PA) - according to the SCHMIDT factory procedure. The diameters are given in
Chapter 2. Any difference in process material size and rigidity from the standard material
may cause a deviation of the accuracy. In 95% of all industrial applications, the SCHMIDT
calibration has been proven to provide the best results and is used for comparative pur-
poses.
Should the process material differ significantly from the SCHMIDT calibration material in
size, rigidity or shape, we recommend special calibration using customer supplied mate-
rial. Please supply a material sample of 5 m for this purpose.
WEIGHT
OUTER ROLLERS
MEASURING ROLLER
PROCESS MATERIAL
SCALE
fig. 3.5
Verification Procedure
:
- Hang a WEIGHT which corresponds to the tension to be measured (pay attention to
the correct unit of measure) from the PROCESS MATERIAL, vertically, as shown in
fig. 3.5. (Always use a fresh portion of the material to be measured.)
- Before verifying the calibration, move the PROCESS MATERIAL slowly up and down to
compensate for possible mechanical friction losses and thus ensure repeatability
of the measurements.
- The tension value shown on the SCALE should be equal to the value of the suspended
weight.
If the verification of the calibration shows a deviation beyond the allowable tolerance and a
reliable operation is no longer allowed, the instrument has to be returned to the factory for
recalibration or servicing.
