MAGUIRE Weigh Scale Blender 4088 TSC, Installation Operation & Maintenance

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Load Cell Raw Signal Readout
Press Setup, System Configuration, Diagnostics, Load-Cell Diagnostics to check this RAW
number for several seconds.
Load cells put out a very small voltage that varies slightly as the load cell is deflected. This
voltage is converted to a pulse train and these pulses are counted for 1 full second to determine a
weight load with a range of counts from 0 to approximately 249,850.
A properly operating set of 3 K cells will range from about 55,000 to 120,000; a span of about
65,000 from empty weight (weigh bin in place), to a full bin weight of 2000 grams. (10 K load cells
range about 90,000 from empty to a full 9000 grams). The system will work correctly as long as
the empty bin weight readout is between 1 and 149,248. 149,248 is the highest number that the
software will accept for zero weight calibration (see parameters, LCZ). If the number is over this
when you press the ZERO weight key, the display will say ZERO LOW.
This RAW COUNT number is converted to the proper gram readout based on load cell calibration
information.
The RAW COUNT numbers are more useful in diagnosing load cell problems because they
bypass the calibration math and, therefore, bypass any calibration errors that might have
occurred.
A floating, drifting number usually indicates the load cells are not plugged in.
A readout of 0 indicates an open circuit, a damaged wire or cell.
A full-scale readout of 249,850 indicates a damaged wire or cell.
A set of 3 K load cells will put out about 33 more counts for every gram of weight that is added. A
test of sensitivity is to add a small weight to the bin. The RAW WEIGHT count should increase by
about 33 counts for each gram added. (10 counts per gram for 10K load cells.)
If you call us for help in solving a load cell problem, it is helpful if you can tell us what the RAW
COUNT number is with the bin empty, and with a known weight in it. To display the RAW COUNT
number for the current weight, go to Setup, System Configuration, Diagnostics, Load Cell
Diagnostics.
To OPERATE with DAMAGED load cells in a VOLUMETRIC mode, see Volumetric Operation on
page 68.