Installation manual

Calibration 25
5.0 Calibration
The calibration procedure maintains the scale accuracy within specifications and can serve as a performance test
procedure. The DC-190 scale should be turned on for a minimum of 10 minutes and the platform exercised three
to four times before attempting to calibrate.
NOTE: Use the SCALE key to select the platform to calibrate. The scale number is displayed on the lower secondary
display. For dual-platform scales, the calibration procedure described in must be repeated for each scale.
Scale Calibration Procedure
Use the following procedure to calibrate the DC-190:
1. Press and hold the
REZERO key and enter
8715 on the keypad to enter calibration mode.
The QUANTITY displays the raw count.
2. With no weight on scale, press the
CODE key
to compute the zero point. The
QUANTITY
display will show a count of approximately
100000. If the QUANTITY display is not
100,000 ±10,000, use the
+ or – key to adjust
until the display is within range or press the
CODE key to automatically recompute zero.
3. Press the REZERO key to zero the weight
shown in the
WEIGHT display.
4. Place a known test weight on scale.
5. Adjust displayed span weight as close as
possible to the known test weight by using
TARE key to increase or PIECES key to
decrease the load cell sensitivity value.
6. If span adjustment is required in Step 5,
remove test weight and repeat Steps 2 through
5.
7. Enter the known calibration weight (including
all trailing zeros) using the numeric keypad.
8. Remove the test weight from the scale to
verify that the zero value has not shifted. If
the value in the
WEIGHT display is not zero
(has shifted), press the
REZERO key.
9. Place the known test weight back onto the
scale. If you had to adjust the zero value you
will notice that the weight value has also
changed and is closer to the true value.
10. Press the
* key to start span calibration. After
a few seconds, the display shows the counts
for the weight on the platter in the
WEIGHT
display and the internal count (including zero
point internal counts) in the
QUANTITY
display.
11. Remove weight from scale. When the
calibration weight is removed, the
WEIGHT
display should show zero and the QUANTITY
display should show the zero starting point.
For example, if SPEC 38, bit 1 (
Internal
Count
) is set to 1,000,000, the count should
be approximately 200,000. If the zero point is
not correct, repeat the calibration procedure.
12. Press the
MODE key once to exit maintenance
mode.
13. Press the
MODE key again to return to the
weighing mode.
14. Place the test weight used to calibrate span
back on scale and verify proper weight. If the
displayed weight value is not equal to the
known test weight, repeat the procedure.
NOTE: If you are using a multiple scale configuration,
repeat the procedure above for each scale. Use the
SCALE key to switch between scales.
Displaying Internal Counts
To display internal counts, press and hold the
REZERO key and enter * * + on the keypad.
Press the
MODE key once to exit maintenance mode,
press
MODE again to return to weighing mode.