ABB REL670 - Current Reversal and Weak End Infeed Logic for Distance Protection (PSCH, 85)

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Scheme communication Chapter 11
Verifying settings by secondary
injection
12.1.5 Completing the test
Continue to test another function or end the test by changing the test mode setting to off.
12.2 Current reversal and weak end infeed logic for distance
protection (PSCH, 85)
Prepare the IED for verification of settings as outlined in section 1 "Overview" and section 2
"Preparing for test" in this chapter.
The current reversal logic and the week end infeed functions are tested during the secondary in-
jection test of the impedance or overcurrent protection zones together with the scheme commu-
nication logic for the distance protection function (PSCH).
12.2.1 Current reversal logic
It is possible to check the delay of the CS carrier send signal with tDelay by changing from a
reverse to a forward fault.
By continuously activating the CR input and changing from a reverse to a forward fault, the de-
lay tDelay can be checked.
Checking of current reversal
Procedure
1. Activate the carrier receive (CRL) signal.
2. Set the healthy condition to an impedance at 50% of the reach of the
reverse zone connected to IRVL.
3. After the start condition is obtained for reverse zone, apply a fault at
50% of the reach of the forward zone connected to WEIBLKL1.
4. Check that correct trip outputs and external signals are obtained for
the type of fault generated.
The operation time should be about the tDelay setting longer than the car-
rier accelerated trip (TRIP) previously recorded for permissive scheme
communication.
5. Restore the forward and reverse zone timer to its original setting.
Note!
The reverse zone timer must not operate before the forward zone fault is applied. The user might
need to block the reverse zone timer during testing of current reversal.
Note!
The forward zone timer must be set longer than 90 ms.