American Weigh Scales (AWS) CP4-650 - Manual (Page 5)

2. Hold the [ UNITS ] key for a few seconds. The
display will show "CAL".
3. Press the key again. "CAL" will flash, followed by
the required calibration weight (ie. 500g).
3. Place the calibration weight onto the platform.
4. The display will show "PASS" then return to normal
weighing mode. Calibration is complete!
V. TROUBLESHOOTING
[Display] Elimination of errors
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[OUT2] Recalibrate the scale (Section IV).
[EEEE] You are overloading the scale. Remove the
excessive load immediately!
[un2T] Use the scale in a more stable position