According to the global weighing standard GWP two test weights are sufficient for balance routine testing:
According to the global weighing standard GWP two test weights are sufficient for balance routine testing: For repeatability testing the recommended test weight is ~5 % of the device's capacity. For sensitivity and eccentricity testing the test weight should normally be 100 % of the device's capacity for laboratory balances and 33 % of the device's capacity for industrial scales. Both weights are rounded down to the next OIML/ASTM denomination. ( Source: Mettler Toledo )