B.4.3 Example 3, calibration procedure using load cell mV/V sensitivity
Manual DAS 72.1
Page 21
3 Leg tank or silo fitted with 3 off
1000 kg @ 2 mV/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 DAS 72.1 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
Situation: The silo is partly filled, a zero point shift (menu 1.2) is not possible. Tare of the silo and load cell
sensitivity are known.
Example: Tare is 600 kg, load cell sensitivity is 2.0000 mV/V. In this case we have to use also 2.0000 mV/V for
3000 kg. This means at tare the signal is 0.4000 mV/V.
Go to Menu 1.3. using the UP/DOWN and RIGHT keys to set the zero point of the 3 load cells to 0.4000 mV/V.
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 2 mV/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.
Calibration is now completed.
