Scale Trouble Shooting (2)

2. Gross Calibration Test
The purpose of this test is to determine if the scale is consistently weighing correctly with each application of weight.

It will help determine if a re-calibration is needed, or if there are other problems with the scale.

A. Arrange for the most amount of test weights that can be loaded on the scale. Ideally this should be a minimum of 20% of the normal weighing range of the scale. The weights should be applied near the center of the scale or evenly distributed on the scale.

B. Empty the scale and re-zero the scale using the zero button on the scale indicator.

C. Apply the test weights to the scale.

D. Record the weight now showing on the scale indicator. This should be equal to the test weight amount +/- .1% of the test weight amount (for legal for trade scales). Non-legal for trade process scales will normally have wider tolerances that may be as much as .5%.

E. Repeat steps B-D at least twice to test for repeatability. If the scale is in error, but repeatable, then re-calibrate it as described in section 5. If the scale is not repeatable in it’s weights, then see next article...............