Circuit breaker is composed as one of electrical power system. As an expensive switch gear, it not only breaks a load current but also a fault current, serving as a practical implementing role in system management, control, and protection.

Thus credibility of circuit breaker activation is directly related to a credibility of other systems connected with. Due to this, effort to prevent circuit breaker and protection system fault should be improved.

Recently, credibility of circuit breaker activation has been improved by development of GIS (Gas Insulation Switchgear). As diagnosis and protection of circuit breaker continuously evolved, at present, various types of verified systems have been applied.

Protection relay for 345 [kV] circuit breaker failure protections uses both over current protection function for diagnosis of circuit breaker condition and circuit breaker failure initiation function (BFI) by circuit breaker control command. Thus it is composed into and applied to a system in order to prevent spread of fault, using both circuit breaker trip commands by protection system and detection of circuit breaker’s abnormal condition.

GABO’s 345 [kV] circuit breaker failure protection panel has a protection relay (7SV600) made from SIEMENS, in order to guarantee reliability. By having accumulated knowledge in manufacturer technology of protection panel, and experienced professionals, we strive to accomplish noise immunity, stable earthing, durability, insulation, assembly, all of which being incorporated in order to generate products of credibility.

CIRCUIT BREAKER FAILURE PROTECTION SYSTEM CONFIGURATION   Circuit Breaker failure protection system detects current flowing through a circuit breaker and an initiating signal for circuit breaker trip command, in order to monitor activation condition of a circuit breaker. When circuit breaker failure gets detected, in order to prevent expansion of fault, circuit breaker failure protection system trips peripheral circuit breakers located nearby circuit breaker with fault.       BREAKER FAILURE PROTECTION RELAY (7SV6x) SPECIFICATION   - Digital Protection Relay with 16 Bit microprocessor - Independent high sensitive current detection on each phase. - Independent indication on each phase / 3 phase common initiation detection. - 2-out-of-4 current detection function - Single- Stage, Two- Stage time delay. - Remote end transfer trip. - Zero Sequence, negative sequence current compensation

	CIRCUIT BREAKER FAILURE PROTECTION RELAY (7SV6x) MAIN FUNCTION

- Circuit breaker failure (current/ circuit breaker condition observation) detection function.	- Remote end transfer trip.
- End Fault protection.	- User defined logic (CFC-continuous function chart).
- Function to prevent mal-function through many fault detection.	- Self-diagnosis
- Selection possible to one pole/three pole trip function	- Metering (current, voltage, active/ reactive power, etc)
- Event recording function (trip, alarm, fail, etc)	- Using any portable computing device, setting and fault analysis function (analysis program (DIGSI), Comrade File conversion function) becomes possible.

	CIRCUIT BREAKER TECHNICAL SPEFICATION/STANDARD

Index	Item		Specification	Remarks
Rating	Power Supply	Voltage Input	DC : 125[V], AC : 230[V](Frequency 50/60[hz])	Selectable
		Power Consumption	4[W]
	Analog	Current	1[A], Burden : 0.1[VA]   5[A], Burden : 0.2[VA]
	Digital input		Number of digital input : 3   Voltage Range : 24 ~ 250[VDC]	Selectable
	Digital Output		Number of digital output : 4   Allowable Current : Continus(5[A]), 30[A](0.5[sec])
Communication	Communication Port		RS-485	Selectable