NCR RealScan 7872 Installation/Owner Guide
497-0415291 Release F
08/04
19 of 44
Step 4 Calibrate the Scale
Note:
The Bizerba computing scale, used in a RealScan 7872-53xx, is calibrated at the
factory and cannot be calibrated in the field. However, you can reset the scale by
turning off the power, then turning it back on with no weight on the Top Plate. If you
are installing a RealScan 7872-53xx with a Bizerba scale do not attempt to calibrate the
scale, but continue to
Step 5 ñ Check the Scanner Operation
.
Note:
You MUST calibrate the scale when you install a RealScan 7872. To be in
compliance with governmental weights and measures regulations, you must be certified
or registered with your government to calibrate and place a weighing instrument into
service.
Note:
Calibration information is NOT sent to the host terminal. If your RealScan 7872
does not have voice enabled or does not have a remote display, you must use a Field
Service Calibration Display.
Caution:
Be sure the Interface Cable between the RealScan 7872 and the host terminal is
disconnected
during scale calibration. Some host terminals can cause interference that
can invalidate the scale calibration.
You can calibrate the scale after power has been supplied for 30 minutes if the ambient
temperature has been 20 C (68 F) for at least 24 hours. If this condition is not met, then
the scale must be on for at least 6 hours before you can calibrate it. Also, you must use a
certified weight set to calibrate and certify the scale.
The EEPROM on the scale board maintains an audit trail of scale calibration and
programming activity. The audit trail records the number of times the scale has been
calibrated. You can display the audit trail count on a Remote 7825 or Field Service
Calibration Display by pressing and holding the Scale Zero Button on the Operator
Display Panel. The display alternates between Cal xxx and Par xxx.
Exercise the Scale
You must exercise the scale before performing a calibration. Add and remove weight to
your scale in the order given in the following chart. This is a building procedure in
which you start with no weight (0) and sequentially add and remove weight to obtain
the values shown in the chart. Go through this procedure four times.
Weight Feature
Total Weight on Top Plate
13.995 kg
0.0 kg
2.5 kg
5.0 kg
15.0 kg 5.0 kg
2.5 kg
0.0 kg
30.0 lb.
0.0 lb.
5.0 lb.
15.0 lb. 30.0 lb. 15.0 lb. 5.0 lb.
0.0 lb.
