• Symmetric three-phase current, where the current is the summation of two currents that have the
same magnitude, but different frequencies.
I I A
tf
t
I
50
2
20918
2
10459= = = =
GUID-F02E8D18-FF87-45BE-8142-E8FA19F6966B V1 EN-US (Equation 20)
The first current I
50
has frequency 50 Hz, magnitude 10459 A (that is, 1.162 A secondary) and
phase angle 0º.
The second current I
tf
has magnitude 10459 A (that is, 1.162 A secondary), phase angle 180º (at the
starting time of the test) and frequency:
• 49.5 Hz for the test as generator in the quadrant 1 and 2 of the R-X plane
• 50.5 Hz for the test as generator in the quadrant 3 and 4 of the R-X plane
When the trajectory of the impedance, that is seen by the protection function, traverses
the lens characteristic then a pole slipping is detected. The present procedure avoids
tests of points of the line SE-RE that are too close to the R-axis because in that case the
voltage is close to zero and, therefore, the impedance may approach a non-defined
quantity 0/0.
The accuracy of the impedance reach is ±2% of the base impedance; that is considered
while evaluating the test results.
For the test as motor the frequency current may have 50.5 Hz in the quadrant 1 and 2 of
the R-X plane and 49.5 Hz in the quadrant 3 and 4.
Verifying the settings by secondary injection
GUID-1752CE04-7C0F-4D37-9602-B22D8096DD2D v1
It is advised to connect the analog output channels of the function block OOSPPAM to the internal
disturbance recorder (and in particular to the function block A4RADR) in order to perform a better
analysis of the tests.
If the device is in test mode, the recording of the disturbances are enabled by the setting in Main menu /
Settings /IED Settings /Monitoring /Disturbance report /DisturbanceReport /DRPRDRE:1: set the
parameter OpModeTest to On.
1. Check the Application Configuration: verify that hardware voltage and current channels of the IED
are properly connected to SMAI function blocks, and that the proper analog outputs of SMAI’s are
connected to the analog inputs of the function block OOSPPAM.
2. Connect three-phase voltage channels of the test set to the appropriate IED terminals.
3. Connect in parallel two groups of three-phase currents of the test set to the appropriate IED
terminals.
4. Connect the appropriate trip output of the IED to the input channel of the test set that monitors the
trip.
5. Go to Main menu /Settings /IED Settings /Impedance protection /OutOfStep(78,Ucos) /
OOSPPAM(78,Ucos):1 , and make sure that the function is enabled, that is, Operation is set to On.
Section 11 1MRK 504 165-UUS Rev. J
Testing functionality by secondary injection
148 Transformer protection RET670
Commissioning manual
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