The Free Calibration provides access to the span calculation screen for precalibration of a scale without test weirghts.       The Free Calibration procedure is applicable for normal precision process control,and it’s forbidden in trade settlement status. Steps: 1.Access to Free Calibration menu: ‘System Setup’→ ‘Maintenance’→ ‘Free Cal’ 2.Enter the load cell capacity and rated load cell output values in the associated fields: The total load cell capacity should be entered here.For example, for a tank with three 5000 kg cells,cell capacity would be 3 x 5000 kg or 15000 kg. 3.Enter the excitation/response rate (mV/V) of the load cell, the sensitivity of load cell,which is usually included in the nameplate of the load cell.The value is always 2.00000mV/V. 4.Empty the scale, perform [Zero Cal] 5.Calibration OK.