ABB REG670 Commissioning Manual page 73

1MRK 502 073-UEN A
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Commissioning manual
Calibrating injection based sensitive rotor earth fault protection
If the second reference impedance shall be defined and the logic to switch from the
first impedance to the second one is already active in the configuration, then set the
second reference impedance equal to the first reference impedance before starting
the procedure in the Commissioning tab. The trip of the function should be
blocked, as advised by the pop-up window of ICT.
A similar approach is advised for the other available reference impedances.
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 values 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.
GUID-FAE32C52-80F0-4AEF-AA0D-6BA39F896712 V1 EN-US
Figure 13:
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.
Measured absolute
Floating average of the
impedance
measured absolute
impedance
Commissioning tab
Section 6
Measured absolute
impedance ± standard
deviation
Reference Impedance
Selection dropdown
menu
IEC11000046-1-en.vsd
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