Instruction manual

Linearization
Conveyor applications where the belt scale is poorly located, or where there is a high
degree of variation in belt tension, typically cause the belt scale to report load
non-linearly. The BW100 provides a linearizing function (P390 - P396) in order to
correct for the deficiency in the weighing system and to provide an accurate report of
the actual process.
To verify that the cause of the non-linearity is not mechanical:
» run the conveyor belt empty and stop it.
» Suspend various test weights to the scale to verify mechanical linearity. If the
load reported by the BW100 at these tests is non-linear, a mechanical problem
is indicated. Refer to the belt scale manual in order to resolve the non-linearity
by improved installation or repair.
If it is determined that the non-linearity is due to the weighing application, and not the
actual belt scale, apply linearization by performing the following:
» zero calibration
» span calibration at 90 to 100% of design rate
» material tests at 90 to 100% of design rate
» manual span adjust if required
» material tests at 1 to 3 intermediary flow rates where compensation is required.
Compensation points must be at least 10% of the design load apart.
E8 message occurs if a point is less than 10% of
full scale or if points are less than 10% apart.
» calculate the percentage compensation for each flow rate tested.
% compensation =
actual weight - totalized weight x 100
totalized weight
where: actual weight = material test
totalized weight = BW100 total
97/07/07
RECALIBRATION
PL-531 45