NCR RealScan 7875-7000 - Step 5 - Calibrate the Scale; Set Scale AC Voltage Frequency; Exercise the Scale

NCR RealScan 7875-7000/8000 Installation Guide
06/03 AIP-00342 Release B
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Step 5 – Calibrate the Scale
Note: You MUST calibrate the scale when you install a RealScan 7875-80xx. To be in
compliance with governmental weights and measures regulations, you must be certified to
calibrate the scale.
Note: Calibration information is NOT sent to the host terminal. If your RealScan 7875 does not
have voice enabled or does not have a remote display, you must use a Field Service Calibration
Display.
Note: Be sure the Interface Cable between the RealScan 7875 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 RealScan 7875 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 the Scale Zero
Button on the Operator Display Panel. The display alternates between Cal xxx and PAr xxx.
Set Scale AC Voltage Frequency
The RealScan 7875-8000 units contain a scale that must be set for the correct AC voltage
frequency before the scale is calibrated.
1. Turn on the AC Power by turning on the circuit breaker.
2. Set the AC voltage frequency by scanning the following sequence of programming tags.
These must be the first tags scanned after applying power to the unit.
60 Hz AC Voltage
Programming Mode, Hex 3, Hex 0, Hex F – Default setting
50 Hz AC Voltage
Programming Mode, Hex 3, Hex 0, Hex E
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
9.995 kg 0.0 kg 2.5 kg 5.0 kg 10. 0 kg 5.0 kg 2.5 kg 0.0 kg
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.