Stub Protection Stbptoc; Identification; Application - ABB Relion 650 Series Applications Manual

1MRK 505 355-UEN A
Protection
operate time
The fault
occurs
IEC05000479 V2 EN-US
Figure 47: Time sequence
t3 : Additional time delay to t2 for a second back-up trip TRBU2. In some applications there
might be a requirement to have separated back-up trip functions, tripping different back-up
circuit breakers.
tCBAlarm : Time delay for alarm in case of indication of faulty circuit breaker. There is a binary
input CBFLT from the circuit breaker. This signal is activated when internal supervision in the
circuit breaker detect that the circuit breaker is unable to clear fault. This could be the case
when gas pressure is low in a SF6 circuit breaker, of others. After the set time an alarm is
given, so that actions can be done to repair the circuit breaker. The time delay for back-up trip
is bypassed when the CBFLT is active. Typical setting is 2.0 seconds.
tPulse : Trip pulse duration. This setting must be larger than the critical impulse time of circuit
breakers to be tripped from the breaker failure protection. Typical setting is 200 ms.
6.10

Stub protection STBPTOC

6.10.1

Identification

Function description
Stub protection
6.10.2

Application

In a 1½-breaker switchyard the line protection and the busbar protection normally have
overlap when a connected object is in service. When an object is taken out of service it is
normally required to keep the diagonal of the 1½-breaker switchyard in operation. This is done
Application manual
Normal t
cbopen
Retrip delay t1 t after re-trip
cbopen
Minimum back-up trip delay t2
Critical fault clearance time for stability
Trip and Start
CCRBRF
t
BFPreset
Margin
IEC 61850 IEC 60617
identification identification
STBPTOC
3I>STUB
SYMBOL-T V1 EN-US
Section 6
Current protection
Time
IEC05000479_2_en.vsd
ANSI/IEEE C37.2
device number
50STB
IP14515-1 v3
M17108-1 v2
M12904-3 v5
103