SHIMPO 921A - Manual (Page 34)

B.2
TRICOR Systems Inc.
Step 5 There are two types of force transducer CCAs which are
illustrated in Figures B.5a and B.5b. Examine your unit's force
transducer CCA to determine which type is on the unit.
Reference figure a or b accordingly to perform the adjustments
of steps 6, 7, and 8.
Step 6 Adjust the force transducer CCA potentiometer labeled "offset"
on Figure B.5 until the offset value displayed on the unit is as
close to the nominal value listed below for your transducer type.
The force offset adjustment must be within the range listed
below for your transducer type for proper calibration.
Type Nominal Acceptable Range
3.6 kg 0.075 kg 0.025 to 0.200 kg
360 g 7.5 g 2.5 to 20.0 g
75 g 1.6 g .5 to 4.2 g
2.0 kg 0.038 kg 0.012 to .100 kg
750 g 15 g 5 to 42 g
50 lb 1.04 lb .35 lb to 2.80 lb
20 lb 0.38 lb 0.12 to 1.00 lb
Step 7 Turn on the force gauge. Select the units (kg or g) and zero the
force gauge. Press the TEST/READY switch once. The unit
drive mechanism will operate until the unit force transducer is in
contact with the force gauge and reaches the calibration force
level. The unit displays the adjust force pot(s) message for
Force = Gauge value and displays
Force = "Measured Value"
Refer to Figure B.5 and adjust the GAIN 1 and/or the GAIN 2
potentiometer until the unit force "Measured Value" is equal to
the force gauge value within the tolerance listed below for your
transducer type.
Adjustment Specification
Type Tolerance Tolerance
3.6 kg ± .003 kg ± .010 kg
360 g ± 0.4 g ± 2.0 g
75 g ± 0.1 g ± 0.5 g
2.0 kg ± .002 kg ± .005 kg
750 g ± 0.8 g ± 3.8 g
50 lb ± 0.04 lb ± 0.25 lb
20 lb ± 0.02 lb ± 0.10 lb