MTS Series 793 - Manual (Page 203)

Item Callout
Shunt Cal Circuit 1
Sensor Bridge 2
Feedback 3
Excitation 4
Shunt Calibration Circuit 5
Series 494 DUCs include an HWI Editor setting that allows you to select the leg of the bridge where the shunt
resistor is applied.
Shunt reference values
Only update the Shunt Reference Value after you perform an official calibration using a laboratory standard
reference sensor. You can then apply the shunt-calibration resistor and update the reference value with the
current shunt value. The reference value should not be changed until the next official calibration.
How to Perform a Shunt Calibration Check
1. In the Station Manager window’s Display menu, click Station Setup.
2. In the Station Setup window’s navigation pane, click the sensor input that requires shunt calibration.
3. Click the Shunt tab.
The Shunt Reference values are also available on the Calibration tab of the Station Signals summary
page.
4. Perform the shunt check.
a) As required, select the Current Range that you want to check.
b) In Select Shunt Type, select either (+) Shunt or (-) Shunt (FlexTest IIm systems only).
c)
Click to apply the shunt.
5. Compare the Current Shunt Value to the Shunt Reference Value.
a) In the Shunt Reference Value list, click mV.
b) Recalibrate the sensor if the Reference and Current values differ by more than 20 mV.
6.
Click to remove the shunt.
Leaving the Shunt tab or choosing another item in the navigation panel will automatically remove the
shunt.
MTS Series 793 Control Software 203
Station Setup