Omega Engineering OMB-DBK-34A, User Manual

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Shunt –
applies a shunt resistor to the bridge to simulate a load.
Shunt calibration is identical to 2-Point calibration except that the second point is simulated so that
applying a load near the gage’s maximum load is unnecessary. To simulate a bridge imbalance, a shunt
resistor is placed across one leg of the bridge. Once the shunt resistor value has been calculated, it is
applied to the bridge to provide the desired simulated load. No gain calculations are required to perform
this calibration method.
Manual
–
used to assign specific gains and offsets.
If a particular gain and offset are already known, these values can be used to setup a strain gage channel.
Procedures Common to All Calibration Steps (Required)
Set the Selected Channel(s) to DC Coupling
Since the applied calibration-signals are DC, set DC coupling for all the channels that are being adjusted.
If your application requires AC coupling , don’t forget to remove the jumpers when the adjustment
procedure has been completed.
Determine Channel Parameters
Before adjusting the trimpots, the excitation needs to be determined. Typically, the supplier of the gage of
load cell will recommend a suitable value, but make sure that the maximum output current of the excitation
regulator is not exceeded.
Initialize LogView
Launch LogView and use the LogBook Hardware Configuration window (hardware tree) to configure all
of the DBK options that are to be used in the system. If needed, refer to the LogView chapter.
LogBook Hardware Configuration, Button and Screen
Open the Analog Input Channel Configuration Window . Click the User Scaling Tab and verify that all of
the strain gage channels that are to be adjusted have scale and offset values of 1 and 0, respectively.
DBK Option Cards and Module
879895
DBK16, pg. 17