Pole Discrepancy Protection Ccrpld (52Pd) - ABB REL650 series Technical Manual

1MRK 506 335-UUS A
7.13
7.13.1
7.13.2
7.13.3
Technical manual

Pole discrepancy protection CCRPLD (52PD)

Identification
Function description
Pole discrepancy protection
Functionality
Circuit breakers and disconnectors can end up with their phases in different positions
(close-open), due to electrical or mechanical failures. An open phase can cause negative
and zero sequence currents which cause thermal stress on rotating machines and can cause
unwanted operation of zero sequence or negative sequence current functions.
Normally the affected breaker is tripped to correct such a situation. If the situation
warrants the surrounding breakers should be tripped to clear the unsymmetrical load
situation.
The pole discrepancy function operates based on information from the circuit breaker
logic with additional criteria from phase selective current unsymmetry.
Function block
CCRPLD (52PD)
I3P* TRIP
BLOCK PICKUP
CLOSECMD
OPENCMD
EXTPDIND
ANSI08000041-1-en.vsd
ANSI08000041 V1 EN
Figure 127: CCRPLD (52PD) function block
IEC 61850 IEC 60617
identification identification
CCRPLD
PD
SYMBOL-S V1 EN
Section 7
Current protection
ANSI/IEEE C37.2
device number
52PD
271