220V power supply, 4.5A is equal to about 1KW, 32A theoretically can carry 7.1KW. actual use, it is recommended that no more than 6KW is appropriate.
Rated operating current 32A, the maximum bai power = 32a * 200v = 7.04kw
Leakage circuit breaker: circuit leakage current exceeds a predetermined value of the switch can be automatically actuated. Commonly used earth leakage circuit breaker is divided into two categories of voltage type and current type, and the current type is divided into electromagnetic type and electronic type. Leakage circuit breaker used to prevent personal electric shock, should be based on direct contact and indirect contact with the two kinds of electric shock protection of different requirements to choose.
Extended information:
Because of direct contact with electrocution is more harmful, caused by the consequences of a serious. So to choose a higher sensitivity of the leakage circuit breaker, electric tools, mobile electrical equipment and temporary lines, should be installed in the circuit of the action current of 30mA, action time within 0.1s leakage circuit breaker. For residential houses with more household appliances, it is best to install them behind the incoming energy meter.
If once electrocuted is easy to cause secondary injuries (such as working at height), should be installed in the circuit with an action current of 15mA, action time within the US leakage circuit breaker. For electrical medical equipment in hospitals, earth leakage circuit breakers with an action current of 6mA and an action time within US should be installed.
Baidu Encyclopedia - Earth Leakage Circuit Breaker