ABB RELION REX640 - Checking binary input and output circuits; Authorizations; User authorization

<U
TC1
-Q0
BI1
+J02 -A1
+J02 -A1
-A1
-F1
Control +
Control -
ES
IRF
TO1
TO2
<U
TC1
-Q0
BI1
+J01 -A1
+J01 -A1
-A1
-F1
Control +
Control -
ES
IRF
TO1
TO2
+J01 +J02
Figure 34: Motor feeder fail-safe trip circuit principle, example 4
J01 Feeder #1 panel
J02 Feeder #2 panel
ES Emergency stop
Q0 Circuit breaker
TO1 Relay trip output #1
TO2 Relay trip output #2
IRF Relay internal fault indication
BI1 Relay binary input #1
<U CB undervoltage trip coil
TC1 CB trip coil 1
F1 Miniature circuit breaker
In example 4, the fail-safe approach aims at securing motor shutdown via an
emergency switch and in case the control voltage disappears. The adjacent panels
provide backup for each other in internal relay fault situations. In case of an internal
relay fault, the situation is noticed by the relay in the adjacent panel and the circuit
breaker in the panel with the faulty relay is tripped after a preset time delay. The
additional time delay allows the relay to recover from the internal fault situation
without tripping the circuit breaker.
3.3.4.2 Other critical feeders
The examples given for motor feeders can be applied for other types of feeders as
well. The following examples are for critical feeders in which the protection system
dependability, security or both are the drivers.
1MRS759142 F
Basic functions
REX640
Technical Manual
113