Verifying Scale Accuracy
Scale accuracy must be verified immediately following calibration, and annual scale inspections are recommended to ensure that weighing error due to harsh environmental conditions and mechanical stresses do not go unnoticed. Inspection periods greater than one year increase risk of weighing error and regulatory non-compliance. Scales must be calibrated when the measured weighing error exceeds the regulated tolerance requirements. For jurisdictions where a government authority does not perform regular inspections, NCR’s inspection service helps maintain customer trust in the brand by ensuring all scales comply with local regulations. Contact your local NCR Service Representative for program details.
Perform the following scale accuracy verification tests in order, immediately after calibration and during an annual inspection.
| Step | Scale Accuracy Test | Description |
|---|---|---|
| 1 | Increasing Load Test | Verifies scale accuracy when incrementally adding weight to the Top Plate, without returning the weight to zero. |
| 2 | Over-Capacity Test | Verifies that proper indication appears on the Scale Display when too much weight is placed on the Top Plate. |
| 3 | Decreasing Load Test | Verifies scale accuracy when incrementally removing weight from the Top Plate, without returning the weight to zero. |
| 5 | Return to Zero Test | Verifies that the scale returns to zero when all weights are removed. |
| 4 | Shift Test | Verifies accurate weight measurement in all quadrants of the Top Plate. |
After verification, record or report audit trail information to the local Weights and Measure authority where required by law.
