The asymmetrical breaking current is the r.m.s. the value of the total current at the INITIAL instant of contact separation and is equal to the square root of the SUM of the squares of the symmetrical breaking current and of the DIRECT COMPONENT of the current at the same instant. The symmetrical breaking current is the r.m.s. the value of the symmetrical current (a.c. component of current) at the initial instant of contact separation. ACTUALLY, the rating of the breaker is specified in terms of symmetrical breaking current & voltage.

The asymmetrical breaking current is the r.m.s. the value of the total current at the initial instant of contact separation and is equal to the square root of the sum of the squares of the symmetrical breaking current and of the direct component of the current at the same instant. The symmetrical breaking current is the r.m.s. the value of the symmetrical current (a.c. component of current) at the initial instant of contact separation. Actually, the rating of the breaker is specified in terms of symmetrical breaking current & voltage.