IN
1)
Magnitude=40mA; Angle=0 degrees
UN Magnitude=75V; Angle=0 degrees
1) Inject set value for IMinReverse+1.5% of CT secondary rated current, (that is0.025A+0.015A when IMinReverse
=2.5% and CT rated secondary is 1A).
3. The following signals that shall be given from the APPTEF function:
• STUN at the beginning of injection.
• STRV after approximately 150ms (default value for tStart=150ms)
The TRIP signal is not issued for EF in the reverse direction.
4. Inject the following analogue quantities given in secondary amperes and volts and wait for three
seconds:
IN
1)
Magnitude=10mA; Angle=0 degrees
UN Magnitude=75V; Angle=0 degrees
1) Inject set value for IMinReverse –1.5% of CT secondary rated current, ( 0.025A-0.015A when IMinReverse =2.5%
and CT rated secondary is 1A)).
5. The following signal is given from the APPTEF function:
• Only STUN at the beginning of injection.
The function did not operate for this reverse EF now because the injected current
is below the set level.
Test of function operation for high-ohmic EF
GUID-99777636-56B6-4B0D-A796-6163B5DE94A2 v1
1. Change the following settings from the default values:
• OperationMode = Start and Trip in order to obtain the trip signal
• IN>=5% (default value)
• IMinForward =50% in order for standard logic not to operate for this test
2. Inject the following analogue quantities given in secondary amperes and volts and wait for three
seconds in order to obtain the trip output (default delay for tTrip=2s):
IN
Magnitude=75mA; Angle=180 degrees
UN
1)
Magnitude=45V; Angle=0 degrees
1) Inject lower voltage than 50V for high-ohmic EF test
3. The following signals shall be given from the APPTEF function:
• STUN at the beginning of injection.
• WRNFW, and STFW after approximately 650ms
• TRIP after approximately 2.65s
1MRK 504 165-UUS Rev. J Section 11
Testing functionality by secondary injection
Transformer protection RET670 203
Commissioning manual
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