B.4.2 Example 2, calibration procedure using load cell mV/V sensitivity and zero offset
Manual DAS 72.1
Page 19
3 Leg tank or silo fitted with 3 off
1000 kg @ 2mV/V load cells
Dead load 600 kg.
Live range 2000 kg in 0.5 kg steps.
It is assumed that the load cell system is
connected to the DAS72.1 and the power is
on. The maximum and minimum display
values, display increment size and decimal
point position should be defined prior to
carrying out the calibration (See Menu 3).
For this example the display maximum is
defined as 2100.0, the display minimum is
-200.0, the display step size is 0.5 kg.
Remember that all parameters under sections 1.1 - 1.3, 2.1 - 2.3 and 3.1 - 3.3 can only be accessed or changed
after the Recessed Enable Switch has been pressed.
a
Go to Menu 1.3. and using the UP/DOWN and RIGHT keys to set the zero point of the 3 load cells to 0.0000
mV/V. Press the 0 [Enter] key. This defines the theoretical zero calibration.
b
Go to Menu 2.1 and using the UP/DOWN and RIGHT keys set the display to read the capacity of the load cell
system or the weight value at which the sensitivity is known. For this example the load cell capacity is 3 x
1000 kg = 3000 kg @ 2 mV/V. Set the display to read 3000.0. Press the 0 [Enter] key. This defines the
theoretical calibration weight (equivalent to 2mV/V in this example).
c
Go to Menu 2.3. Press the 0 [Enter] key. Use the UP/DOWN and RIGHT keys set the display to read the mV/V
sensitivity of the load cell system you are using. For this example the load cell sensitivity or Output at Rated
Load is 2.000 mV/V. In multiple load cell installations (load cells wired in parallel) the sensitivity is the
average of all the load cells connected. Press the 0 [Enter] key. This defines the theoretical span calibration
point.
d
If required the zero can be re-calibrated without affecting the span. To do this make sure that the weighing
system is empty or at the point where you want the display to read zero. Goto Menu 1.2. Press the 0 [Enter]
key. The display shows the actual input signal in mV/V. Press the 0 [Enter] key. Press the right arrow key
twice and the DAS will be back in weighting mode.
Calibration is now completed.
