ABB RELION REB500 Technical Manual page 77

1MRK 505 406-UEN B
Signal
SOTF_INI
START_SOTF
SOTF
Short-zone logic (STUB)
In 1½ breaker schemes, the short zone between the two circuit-breakers and the line isolator
can be protected by the backup overcurrent function by permitting its instantaneous pick-up
signal [TRIP_OC_L1L2L3] to trip the circuit-breakers [TRIP_STUB] after 25 ms whenever the line
isolator is open (signal applied to the optocoupler input Isolator open).
This arrangement is only necessary, if the VTs are installed on the line side of the isolator and
the CTs are in the bars between the circuit-breakers.
ISOL_OPEN
TRIP_OC_L1L2L3
IEC19000423 V1 EN-US
Figure 22: STUB segment
Table 54: Signals VT STUB (see above diagram)
Signal
ISOL_OPEN
TRIP_OC_L1L2L3
TRIP_STUB
Zone extension logic (ZE)
This logic enables a signal from another function or an external signal to switch the reach of
the first distance zone from the underreaching to overreaching [BIT_TRIP_ZE].
Such a signal can originate, for example, from the internal auto-reclosure function (binary
input ZExtensionAR [AR_ZE]) or from an optocoupler input (binary input ZExtension [ZE_FOR_
DIST]).
The internal autoreclosure function issues an overreach signal [AR_ZE] when all the
autoreclosure conditions are fulfilled.
Bay protection functions REB500
Technical manual
In Out Source
X Always = 0,
when SOFT = Off
when SOFT = Non-directional
SOTF_INI = (Starter! = 0)
when SOFT = Forwards OR
SOTF_INI = (Starter! = 0) &
(fault in overreach zone)
X
X
AND
25
18000021-IEC19000423-1-en.vsdx
In Out
X
X
X
© Copyright 2019 ABB. All rights reserved
TRIP_ST UB
Source
Binary input: Isolator open
Binary signal: Trip O/C
Section 5
Bay protection functions
Drain
Binary signal: SOFT
picked up
Binary signal: SOFT
starting signal
GUID-9988E657-D310-4C53-B57B-4707C9A89623 v1
Drain
Binary signal: Trip Stub
GUID-732C90E0-C051-498E-8E01-B8BAEF2D48A1 v1
71