... 10,16,20,25,32A 4. SAA certificate Single Pole Circuit Breaker RCBO 4.5kA:Scope of application ... (electric shock), overload, short circuit and so on protection functions. The over voltage protection function can ... at random during usage.2. After using RCBO for a certain time (normally one month), test button ... (press test button once, the RCBO can break off once ). If abnormal, it should be unloaded and ...