ABB REX 521 Technical Reference Manual, Standard Configurations page 136

REX 521
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136
Protection Relay
Technical Reference Manual, Standard Configurations
TRIP circuit breaker
CLOSE circuit breaker
Blocking signal to incoming
feeder (START 3I>>)
Circuit-breaker failure
protection
Definite trip alarm
Internal relay fault
Blocking signal from
the residual voltage relay
to the Io>
External reclosure
initialization signal
1MRS 751802-MUM