Checkline EDM - Manual (Page 3)

3
2.0 O VERVIEW
2.1 Operating Elements
2.2 Mounting Special Finger Support
Whenever useful and necessary, the tension meter is supplied with a special
finger support. We recommend mounting the finger support when measuring
high tension to reduce the necessary effort to move the outer rollers with the
Thumbpiece on the front of the tension meter and facilitate acquisition of the
wire to be measured. Place the special finger support in the recess located on the
rear side of the tension meter and fasten it with the finger support screw.
Thumb piece
Measuring
roller
Process
material
Scale
Guide
rollers
❙ ✁✂ ✄
al finger support
Finger support screw
Thumb piece
6
4.1 Frequency Of Calibration Verification
Frequency of calibration accuracy verification depends on many factors. These
include frequency and extent of tension overloads, operating speeds, length of
operating times, environment, care in handling, etc. Such determination is best
made by the user’s Quality Assurance Department based on the user's experience.
However, a quick calibration check near the anticipated process tension levels
should be done to confirm the integrity of the instrument, as follows:
1. At the beginning of each work session.
2. Every time a unit is dropped.
3. Whenever process readings seem to be out of tolerance for no apparent
reason.
The quick check can be made with a simple load stand, as shown section 4.2,
using a sample of the process material and weights that are close to the tensions
encountered in the process. Be sure to move the tension meter up and down
slowly to simulate the motion of the running process material. This will check
the condition of the guide roller ball bearings and remove any inertia effect of
the movement. Readings that change with this motion reversal may indicate the
possibility of a guide roller ball bearing problem.
In the case of wire, which might be slightly deformed by the action of the
3- roller system during static measurement, always move to a fresh portion
of the wire each time a measurement is made. (In production, the instrument
always “sees” a fresh portion.)
4.2 NIST Calibration
While all DX2-EDM instruments are furnished with a Calibration Certificate
which certifies that they have been calibrated in accordance with factory
procedures and were found to meet all published accuracy specifications,
such calibrations do not fulfill ISO-9000 requirements since no record of
measured values are kept or are submitted. Where ISO-9000 requirements
are to be met, NIST calibration is optionally available but must be specified
at time of order placement or after repair.