One-and-a-half breaker arrangement needs use of three circuit breakers for two circuits. Any circuit breaker can be switched-off for the purpose of maintenance, without the provision of by pass.
The number of circuit-breaker per circuits is 1 1/2 hence the name
It has 2 bus-bar sets I and II. In 1 1/2breaker arrangement, circuit I and circuit II can take supply either from bus-bar I or bus bar II. Thus, this arrangement gives high security against loss of supply.
Such arrangement is particularly suitable for the switch yards in large generating stations in which very high power is to be handled by individual circuits 1 breaker arrangement used 12 circuit breaker more per circuit. Recently circuit breaker arrangement has been used in 400 kV, 750 kV substation.
