As noted above the effect of gravity varies throughout the globe. A precision Digital Electronic Scales should be calibrated once it is located in your facility. Where you locate it is extremely important, and once it is located it should not be relocated without being recalibrated at the new location.
Other accuracy-maintaining criteria include (but not limited to):
Avoiding vibrations from outside or inside traffic transmitted to the Digital Electronic Scales via its work surface. Vibration insulation is an option if a stable work surface is not readily available.
Avoiding drafts and temperature extremes. Certain precision balances have standard or optional draft shields. But in all cases extreme fluctuations in ambient temperature should be avoided such as proximity to direct sunlight or HVAC vents.
Following instructions regarding stabilization time, warm-up time and other criteria before beginning your weighing exercise. Moved or newly installed precision digital scales may require several hours to warm up. Details are provided in manuals. But as an example the Kern 572 model noted above requires a 3-second stabilization time and a 2-hour warm up time.
Good housekeeping. As we say, a clean precision scale is a happy precision scale. Maintenance procedures are spelled out in user manuals.
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