Distribution board bus bar module having leakage current limiting function

A distribution board bus bar module having a leakage current limiting function, the distribution board bus bar module comprising:

• a main bus bar made of a conductive material, which is connected to an output side of a main circuit breaker that blocks power distributed from a three-phase four-wire cable of a three-phase power system and includes a first-phase main bus bar, a second-phase main bus bar, a third-phase main bus bar, and a neutral main bus bar respectively connected to an output terminal of a first-phase voltage line (R line), an output terminal of a second-phase voltage line (S line), an output terminal of a third-phase voltage line (T line), and an output terminal of a neutral line (N line) of the main circuit breaker;
• a plurality of sub-bus bars made of a conductive material, which are connected between the main bus bar and input sides of a plurality of sub-circuit breakers that block power distributed to terminal loads and include a first-phase sub-bus bar connected between the first-phase main bus bar and an input terminal of a first-phase voltage line (R line) of each sub-circuit breaker, a second-phase sub-bus bar connected between the second-phase main bus bar and an input terminal of a second-phase voltage line (S line) of each sub-circuit breaker, a third-phase sub-bus bar connected between the third-phase main bus bar and an input terminal of a third-phase voltage line (T line) of each sub-circuit breaker, and a neutral sub-bus bar connected between the neutral main bus bar and an input terminal of a neutral line (N line) of each sub-circuit breaker;
• and
• a neutral main bus bar area expansion unit that is in electrical contact with the neutral main bus bar of the main bus bar to expand an area of the neutral main bus bar so as to limit a leakage current.