TM 5-3895-374-24-1CalibrationwithWeightsNoteYou must set the following Parameters before initially adjusting the Dead Load or Span.[11] [SELECT] SetLoadCellFullScaleOutput.This parameter represents the output of the load cell, inmillivolts, at maximum scale capacity This entry acts as acoarse span or span range adjustment for the indicatormatching it with the working range of the load cell. Thisvalue must be set accurately to achieve the ratedperformance from the indicator.You may use one of two methods for determining the valueof this parameter - the formula or the trial and error methodFormula:The formula for determining the output of the load cell is asfollows:AmountofLoadCellUsedRated Millivolt OutputLoad Cell Capacityof Load Cell at Capacitye.g.Using a 1,000 lb. Load Cell of 3 mv/v range andestimating you are using 40% of the cell capacity, youwould obtain the formula400 Lbs.1000 Lbs. X 3 x 9= 10.8Round this off the nearest integer number, i.e. 11, andenter this value, e.g. press [1] [1] (ENTER].Note:Only integer numbers from 8 to 35 may be entered for this value.TrialandErrorMethodIn this method you will try various values for this parameter and seewhat the resultant scale readings are1.First make sure that the scale and load cells are wired up correctly.Then press the (WEIGHTS/COUNTS) key. The flashing ’[’ in theleftmost display digit will be replaced by a flashing ’A’ and a numbershould appear. The indicator is now in the Counts mode. Make surethe scale is clear of weight and note the value of this number. Thisnumber represents the internalrawcounts. If a number does notappear and the display shows ’uuuuuu’ check the TroubleshootingSection VI. For exampleScale clear of weight - internalrawcounts are 34312.Apply a known weight on the scale that represents a fraction of scalecapacity and note the change in the reading. For exampleScale capacity is 5,000 lbs.Apply 1,000 lbs. (1/5 of capacity) -internalrawcountsare 11223.Changein reading is 11223 - 3431 = 7782The indicator has 60,000 internalrawcounts available and, formaximum performance, you want the internalrawcounts to bebetween 50.000 and 60,000 at scale capacity Therefore, at 1/5thcapacity (above example), the change in the internalrawcountsshould be between 10,000and12,000counts.Checking the current value for Parameter 11:[11] [SELECT] --> displayed value = ’14’You must change this value until the above procedure gives you achange in internal raw counts of between 10,000 and 12,000 counts.In this example you must decrease the value of Parameter 11.Note:DecreaseParameter 11 to increasethe changein counts.IncreaseParameter 11 to decreasethe changein counts.For example: Press [11] [SELECT] --> displayed value = ’14’Change to ’12’, press [1] [2] (ENTER).(page 3-64)XX