ABB Relion 650 Series Applications Manual page 97

1MRK 505 287-UUS B
Protection
operate time
The fault
occurs
ANSI05000479 V3 EN-US
Figure 35: Time sequence
7.5 Pole discrepancy protection CCRPLD (52PD)
7.5.1 Identification
Function description
Pole discrepancy protection
7.5.2 Application
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.
Busbar protection REB650
Application manual
Normal t
cbopen
Retrip delay t1 t
cbopen
Minimum back-up trip delay t2
Critical fault clearance time for stability
Trip and Pickup
CCRBRF
(50BF)
© Copyright 2013 ABB. All rights reserved
after re-trip
t
BFPreset
Margin
IEC 61850 IEC 60617
identification identification
CCRPLD
PD
SYMBOL-S V1 EN-US
Current protection
Time
ANSI05000479_3_en.vsd
ANSI/IEEE C37.2
device number
52PD
Section 7
IP14516-1 v4
M14888-1 v3
M13270-3 v5
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