Theoretical Adjustment - Siemens Siwarex U Device Manual

4BWEIGHING FUNCTIONS

5.3 Theoretical adjustment

If performing the adjustment is not possible using adjustment weights, the scale
can also be put into operation without adjustment weights, assuming the
mechanical structure of the scale is correct and the measuring logs are available
for the individual load cells. The execution takes place with the aid of SIWATOOL
U in the processing of the adjustment parameters. We call this procedure
"theoretical adjustment".
First, the characteristic value range (1mV/V, 2mV/V or 4mV/V) must be defined in
the "Weighing parameters" tab of the data record for the adjustment data. Then
switch to "Theoretical adjustment" tab.
To perform the theoretical adjustment, first of all the rated load of all load cells is
specified, e.g. 3 load cells with 1000 kg each produce a rated load of 3000 kg.
Then the adjustment zero offset (unit μV/V) and the characteristic value (unit mV/V)
for each individual load cell is entered. These values are taken from the respective
load cell measurement log. The characteristic value is generally entered with up to
5 decimal places, e.g. 2.01201.
After the entry of the data for each load cell, the adjustment digits are calculated by
pressing the button "Calculate adjustment digits" and the result is displayed. Then
the calculated adjustment digits can be adopted into the data record with
adjustment data (DR 3 and/or DR 4) by pressing the button "Accept calculation".
Then the data record with the new adjustment data is sent to the weighing module.
Depending on the mechanics of the device, a completely empty scale may indicate
a value that deviates from the adjustment zero slightly. In this case the command
"Adjustment zero shift/Set to zero (3)" can be executed.
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SIWAREX U