Checkline EDM - Manual (Page 4)

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1. Prior to engaging the material under test, part the 3-roller system by pushing and
holding the Thumbpiece forward—see arrow above.
2. Keeping the outer rollers extended, bring the instrument behind or under the
wire and move it so that the process material is in contact with V-groove of the
bottom sensing roller.
3. Slowly release pressure on the Thumbpiece until the outer rollers return to their
original position. This will automatically direct the material into the guide roller
grooves.
4. The scale pointer will show line tension directly in grams or kilograms.
Removal
1. To remove the instrument from the process material, push the Thumbpiece
forward again to open the 3-roller system. With the outer rollers extended,
move the instrument away from the material.
2. Remove the instrument and SLOWLY release pressure on the Thumbpiece,
allowing the outer rollers to return to their original position.
CAUTION
Do not let the Thumbpiece snap back as this
may affect calibration and also damage the
instrument.
3.0 T AKING A M EASUREMENT
Thumb piece
Guide rollers
Measuring
roller
Process material
Guide rollers
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4.0 V ERIFYING C ALIBRATION
1. Suspend a known weight that corresponds to the tension to be measured
(pay attention to the correct unit of measure) from the process material,
vertically, see figure above.
NOTE: Always use a fresh portion of the material to be measured.
2. Push the thumbpiece as far as it will go in the direction indicated by the
arrow and thread the material to be measured between the guide rollers and
the measuring roller. Refer to Section 3.0.
3. Slowly release pressure on the thumb piece until the outer rollers return to
their original position.
4. Before the final check, move the instrument slowly up and down to
compensate any friction caused by the instrument and thus ensure
repeatability.
5. The tension value should be equal to the value of the suspended weight.
If this procedure shows a deviation beyond the allowable tolerance and a
reliable operation is no longer allowed, the instrument has to be recalibrated
or repaired. For recalibration, return the tension meter to the factory.
KNOWN
WEIGHT