ABB REG670 2.0 IEC Commissioning Manual page 84

Section 7
Calibrating injection based 100% stator earth fault protection
78
1. Ensure that the generator is in a state where the reference must be set (for
example normal operation).
2. To start, select the Commissioning tab.
3. In the Reference impedance selection drop-down menu. select Reference 2.
4. To start reading the measurements, click the Start reading from IED button in
the ICT toolbar.
ICT starts to read the selected viewed quantity from IED and plots values on the
X/Y graph.
Measured absolute
impedance
GUID-FAE32C52-80F0-4AEF-AA0D-6BA39F896712 V1 EN
Figure 24: Commissioning tab
Normally continuous readings are performed and the read absolute impedance is
viewed in the plot.
By observing the standard deviation of the measured impedance, the
commissioning engineer can decide if the impedance of the generator is stable/
settled, and also if the average impedance is based on enough values so that
statistically the signal noise is "filtered out". This results in a fairly accurate
impedance measurement which can be used as an alternative reference.
5. Click the Select button when the standard deviation has converged so that its
magnitude is within the noise level of the measured absolute impedance.
In the second commissioning sub tab, Step2 : Save Reference Impedance, the
measured real and imaginary reference 2 impedance is presented.
6. Select the Submit to Parameter setting button.
This forwards the newly acquired reference to Parameter setting.
7. Write the newly acquired real and imaginary parts of Reference 2 to IED.
Measured absolute
Floating average of the impedance ± standard
measured absolute
deviation
impedance
Generator protection REG670 2.0 IEC
Commissioning manual
1MRK502053-UEN B
Reference Impedance
Selection dropdown
menu
IEC11000046-1-en.vsd