HBM WE2108 Series, Справочное руководство

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WE2108
HBM A1632-2.0 en
The method is suitable:
•
when building several equal scales,
•
for restoring the calibration after inadvertent deletion. A prerequisite is that
the original values have been noted,
•
for calibrating with calculated values.
Proceed as follows:
•
Select ”CAL−...” parameter in the CAL menu and display with ENTER .
•
Then do not press ENTER but UP . The value can then be changed with UP
and NEXT (operating steps as in the other parameter entries). It must be
stated in mV/V (2,0000 = 2 mV/V).
•
Press ENTER to store the value. donE appears as confirmation.
Cancellation is also possible with CE .
6.4.1 Calibrating with calculated values
In the case of scales for large nominal loads, calibration with calibration
weights is frequently not possible. Since the WE2108 is calibrated in the fac-
tory to an input range of 2 mV/V, the user characteristic can also be deter-
mined by reference to the known nominal value of the load cells. For this pur-
pose the zero value is determined by automatic measuring, but the nominal
value by manual entry.
Calculating the signal span:
Signal span
+
Load cell sensitivity
@
Scale nominal load (
I
CAP 1
I
)
Load cell nominal load
CAUTION
The signal span obtained in this way (in mV/V) is the difference between
the signals at unloaded scale and at nominal load. The measured value
at dead load (”CAL−0”, determined in the calibration with unloaded scale)
must be added to this value before it is stored as ”CAL−1”.
”CAL−1” = calculated signal span + ”CAL−0”
(”CAL−1” is the actual measured value in mV/V, not the signal span).
Enter the nominal load of the scale as ”LOAd1” parameter (= ”CAP 1”).
Scales with several load cells deliver the nominal output signal if the sum of
all load cell nominal loads is placed on as weight.