NCR 7870 User Manual page 88

5-2 Chapter 5: Calibration
The calibration procedure sets the Load Cell and the electronics to
interpret the weight of an item accurately. You can calibrate the scale
after power has been supplied for 30 minutes if the ambient air
conditions have been 20° C (68° F) for at least 24 hours. If the ambient
air conditions have not been met, then the scale must be on for at least
6 hours before you can calibrate it. One or more certified weight sets
are required to calibrate and certify the scale.
The EEPROM on the Scale Board maintains an audit trail of scale
calibration and weigh parameter setting. The audit trail consists of two
event counters. You can display the audit trail count by pressing and
holding the Scale Zero button on the Operator Display Panel. The
display alternates between Cal xxx and PAr xxx. The Cal value is the
number of times the scale has been calibrated. The PAr value is
associated with the weigh parameter setting and should never change.
Note: The audit trail can be displayed only on units with the Integrated
Display or with the NCR 7825 Remote Display.
Whole Pound Weight Set: NCR Part Number 998-0633009
Fractional Pound Weight Set: NCR Part Number 998-0633012
Kilogram Weight Set: Obtain locally