Verifying Calibration - ABB REG670 Commissioning Manual

1MRK 502 073-UUS A
7.6
Generator protection REG670 2.2 ANSI and Injection equipment REX060, REX061, REX062
Commissioning manual
Calibrating injection based 100% stator earth fault protection
Measured absolute
impedance
GUID-FAE32C52-80F0-4AEF-AA0D-6BA39F896712 V1 EN-US
Figure 23: 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.

Verifying calibration

After the calibration is performed, it is appropriate to verify that known faults are
measured as expected and that the function is indicating trips and alarms when it
should, in other words that the calibration was successful. For this purpose the
monitoring feature can be used.
Measured absolute
Floating average of the impedance ± standard
measured absolute deviation
impedance
Reference Impedance
Selection dropdown
menu
GUID-3805BA77-6369-4798-8E1B-1201A0B9C68A v2
Section 7
IEC11000046-1-en.vsd
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