Linearization - Siemens Milltronics BW100 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:
1. Run the conveyor belt empty and stop it.
2. 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.
Notes:
• 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
Where: actual weight = material test
totalized weight = BW100 total
7ML19985DJ01 Milltronics BW100 - INSTRUCTION MANUAL
totalized weight
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