Identification - ABB REL650 Applications Manual

1MRK 506 334-UUS A
7.10
7.10.1
7.10.2
Application manual
TripTemp: Temperature value for trip of the protected circuit. For cables, a maximum
allowed conductor temperature is often stated to be 190°F (88°C). For overhead lines, the
critical temperature for aluminium conductor is about 190-210°F (88-99°C). For a copper
conductor a normal figure is 160°F (71°C).
AlarmTemp: Temperature level for alarm of the protected circuit. ALARM signal can be
used as a warning before the circuit is tripped. Therefore the setting shall be lower than the
trip level. It shall at the same time be higher than the maximum conductor temperature at
normal operation. For cables this level is often given to 150°F (66°C). Similar values are
stated for overhead lines. A suitable setting can be about 60°F (16°C) below the trip value.
ReclTemp: Temperature where lockout signal LOCKOUT from the protection is released.
When the thermal overload protection trips a lock-out signal is activated. This signal is
intended to block switch in of the protected circuit as long as the conductor temperature
is high. The signal is released when the estimated temperature is below the set value. This
temperature value should be chosen below the alarm temperature.
Breaker failure protection 3-phase activation and output
CCRBRF (50BF)

Identification

Function description
Breaker failure protection, 3-phase
activation and output
Application
In the design of the fault clearance system the N-1 criterion is often used. This means that
a fault needs to be cleared even if any component in the fault clearance system is faulty.
One necessary component in the fault clearance system is the circuit breaker. It is from
practical and economical reason not feasible to duplicate the circuit breaker for the
protected component. Instead a breaker failure protection is used.
Breaker failure protection, 3-phase activation and output (CCRBRF, 50BF) will issue a
back-up trip command to adjacent circuit breakers in case of failure to trip of the "normal"
circuit breaker for the protected component. The detection of failure to break the current
IEC 61850 IEC 60617
identification identification
CCRBRF
3I>BF
SYMBOL-U V1 EN
Section 7
Current protection
ANSI/IEEE C37.2
device number
50BF
229