Could you please let me know why electricians use RCD and RCD/MCB s at the same time on the switchboard?
RCD/MCB
- Thread starter Teddytod
- Start date
MCBs ("fuses") provide overcurrent protection and protect the cable from overheating/setting fire
RCDs provide Earth leakage detection ie where power is going somewhere other than where it should (L->N) eg L>E, N>E
RCDs provide Earth leakage detection ie where power is going somewhere other than where it should (L->N) eg L>E, N>E
Actually I mean, RCD/MCB (RCBO) protects circuit against Earth leakage and over-current at the same time, so why between main switch and RCD/MCB, electricians again use RCD?
You don't tend to use RCBOs and seperate RCDs together. RCBOs are more expensive than MCBs but provide earth leakage protection for the individual circuit they are on. 1 RCD plus MCBs are cheaper but all circuits on the same RCD will go down if it trips.