Adam Equipment ACBplus Series, Руководство по обслуживанию

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@Adam Equipment Company 2005 21
With a mass on the load cell the output voltage should increase. The amount it
increases will be dependent upon the sensitivity of the load cell, capacity of the load
cell, the excitation voltage and the amount of mass placed on the load cell. Most
load cells have a sensitivity of either 1mv/V, 2mv/V or 3mv/V.
The expected change to the output is:
Vout = (2mv/V) * Vext * Mass
capacity of load cell
For example a 2mv/V load cell of 30Kg capacity with 20Kg placed on it. Vext is 5
volts would give a output of approximately:
Vout = (2mv/V) * Vext * Mass = 2mv/V * 5V * 20Kg = 6.7mv
capacity of load cell 30kg
If the load cell has been damaged the no load voltage will likely be greater than 3mv
or the loaded voltage will be grossly different from the expected value. Remember
the loaded voltage will be offset by the amount of zero load voltage measured.
The load cell can be tested while it is connected to the A/D converter circuit board,
using the scale power supply for excitation voltage.
TESTING LOAD CELLS IN THE SCALE
Measure the voltage across S- and S+ with a Voltmeter. The reading should be 0mV
with no load and 5mV with full load.