Breaker failure protection
RAICA is suitable as a stand-alone protection or can be integrated in a busbar protection. It provides local backup protection when the primary breaker fails to operate.
RAICA is required to rapidly initiate fault clearing by power circuit-breakers when, for example, a short-circuit occurs in the power system, consequencly isolating the faulty section of the system.
Depending on type, this breaker failure relay consists of a test switch, three current relays, one or two time relays, an impulse storing device, an output relay and an auxiliary relay with flag or a signal relay.
Please also refer to the modern microprocessor based breaker failure relays RXHL 4xx and RAHL 4xx.
Main features are:
- Initiates tripping of adjacent backup breakers for disconnection of the fault, thus preventing power system instability
- Start verifier provides re-trip or cross-trip of primary circuit-breaker for security and reliability after initiation by trip signal
- Very short operating times due to the fast reset time of the overcurrent detectors