We are trying to perform a hard calibration using 3000 lbs test weights. After Hard Cal our Hardy controller reads 3002 lbs with 3000 lbs applied, 1999.3lbs with 2000 lbs, and 995 lbs with 1000 lbs. At 0.0 the unit will not display a tenth of a pound without first applying about 8 lbs. When we suspend a test weight of 30 lbs on the cell the controller reads only 22 lbs. Why is there an error?
When I used to calibrate a 4000 lb cell on our older HI 2151/20WC, we never saw more than a few tenths of a pound error throughout the test range 0-3000 lbs. Why the difference between the HI 2151/20WC and newer controllers?