
5.7
Date Code 20060320
Instruction Manual
SEL-311C Relay
Trip and Target Logic
Switch-Onto-Fault Trip Logic
Switch-Onto-Fault Trip Logic
Switch-Onto-Fault (SOTF) trip logic provides a programmable time window
for selected elements to trip right after the circuit breaker closes. “Switch-
onto-fault” implies that a circuit breaker is closed into an existing fault
condition, such as when safety grounds are accidentally left attached to a line.
If the circuit breaker is closed into such a condition, the resulting fault needs
to be cleared right away and reclosing blocked. An instantaneous element is
usually set to trip in the three-pole open (3PO) logic and the SOTF trip logic.
Refer to the switch-onto-fault trip logic in
(middle of figure). The
SOTF trip logic permits tripping if
both
the following occur:
➤
An element asserts in SEL
OGIC
control equation trip setting
TRSOTF
➤
Relay Word bit SOTFE is asserted to logical 1
Relay Word bit SOTFE (the output of the SOTF logic) provides the effective
time window for an element in trip setting TRSOTF (e.g., TRSOTF = 50P2) to
trip after the circuit breaker closes.
and the following discussion
describe the three-pole open (3PO) logic and the SOTF logic.
q
;
w
to
;
e
to
;
r
.
Figure 5.3
Three-Pole Open Logic (Top) and Switch-Onto-Fault Logic (Bottom)
0
3POD
3PO
50L
OPO = 27
27PO
(Setting)
52A
OPO = 52
_
+
|V1|
+
_
+
_
+
_
50LP
(Setting)
I
A
I
B
I
C
52AEND
SOTFD
CLOEND
0
52AEND = OFF
(Setting)
CLOEND = OFF
(Setting)
CLMON
(SEL
OGIC
Setting)
0
SOTFD
SOTFE
to Trip Logic
e
and CCVT Transient
Blocking Logic
r
Rising Edge Detect
Monitor DC Close Bus
Relay
Word
Bits
To POTT Logic
q
and LOP Logic
w
and CCVT Transient
Blocking Logic
r
Содержание SEL-311C
Страница 1: ...20060320 SEL 311C Relay Protection and Automation System Instruction Manual PM311C 01 NB ...
Страница 22: ...This page intentionally left blank ...
Страница 42: ...This page intentionally left blank ...
Страница 68: ...This page intentionally left blank ...
Страница 128: ...This page intentionally left blank ...
Страница 294: ...This page intentionally left blank ...
Страница 330: ...This page intentionally left blank ...
Страница 402: ...This page intentionally left blank ...
Страница 406: ...This page intentionally left blank ...
Страница 454: ...This page intentionally left blank ...
Страница 574: ...This page intentionally left blank ...
Страница 592: ...This page intentionally left blank ...
Страница 616: ...This page intentionally left blank ...
Страница 648: ...This page intentionally left blank ...
Страница 652: ...This page intentionally left blank ...
Страница 678: ...This page intentionally left blank ...
Страница 682: ...This page intentionally left blank ...
Страница 722: ...This page intentionally left blank ...
Страница 724: ...This page intentionally left blank ...
Страница 732: ...This page intentionally left blank ...
Страница 748: ...This page intentionally left blank ...