ABB Relion REC670, Applications Manual

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setting Continuous the function is activated independent of presence of any external
release signal.
IPickup : Current level for the Stub protection, set in % of IBase . This parameter should
be set so that all faults on the stub can be detected. The setting should thus be based on
fault calculations.
t : Time delay of the operation. Normally the function shall be instantaneous.
8.11 Pole discrepancy protection CCPDSC(52PD)
IP14516-1 v5
8.11.1 Identification
M14888-1 v4
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Pole discrepancy protection CCPDSC
PD
SYMBOL-S V1 EN-US
52PD
8.11.2 Application
M13270-3 v6
There is a risk that a circuit breaker will get discrepancy between the poles at circuit
breaker operation: closing or opening. One pole can be open and the other two closed,
or two poles can be open and one closed. Pole discrepancy of a circuit breaker will
cause unsymmetrical currents in the power system. The consequence of this can be:
• Negative sequence currents that will give stress on rotating machines
• Zero sequence currents that might give unwanted operation of sensitive ground-
fault protections in the power system.
It is therefore important to detect situations with pole discrepancy of circuit breakers.
When this is detected the breaker should be tripped directly.
Pole discordance protection CCPDSC (52PD) will detect situation with deviating
positions of the poles of the protected circuit breaker. The protection has two different
options to make this detection:
• By connecting the auxiliary contacts in the circuit breaker so that logic is created,
a signal can be sent to the protection, indicating pole discrepancy. This logic can
Section 8
1MRK 511 401-UUS A
Current protection
212 Bay control REC670 2.2 ANSI
Application manual