5
CALIBRATION
Calibration of this instrument should remain stable over a long period of
time and over an extended range of voltage and temperature. However, a
calibrated step tablet is provided (inside front cover) to verify the
instrument calibration. Handle the step tablet with care to prevent
accumulation of dirt and fingerprints on the surface.
CALIBRATION FREQUENCY
Under normal operating conditions, the instrument calibration should be
verified
once a week
by the following the Calibration Procedure.
CALIBRATION PROCEDURE
See illustrations on the following page for calibration adjustment locations
and reference.
To verify calibration:
1. Null the instrument as described in
Nulling (Zeroing) Procedure
page
1. Center the “CAL” portion of step tablet under read head.
2. Press read button to measure step tablet.
3. Hold read button down until a stable reading is attained.
•
The “CAL” reading should be ±0.02D of the “CAL” value marked
on the step tablet.
If “CAL” reading is NOT within tolerance, calibrate instrument.
To calibrate instrument:
1. Center the “CAL” portion of step tablet under the read head .
2. Press
and
hold read button to measure the step tablet.
3. Use a small screwdriver or adjustment tool into hole on the right side
of instrument, to engage the calibration adjustment (potentiometer).
4. With read button still depressed, adjust as necessary to within ±0.02D
of the “CAL” value marked on the calibrated step tablet.
•
Rotate counterclockwise to increase value, clockwise to decrease.
5. Remove step tablet and press read button to check null, re-null the
instrument as necessary.
6. Repeat until the calibration value and null are within tolerance.
NOTE:
Always return the step tablet to the plastic bag on inside
front cover for protection.
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