It trips the circuit when there is earth fault current.
RCDs are an extremely effective form of shock protection.
The amount of current flows through the phase (line) should return through neutral .It detects by RCD.
Any mismatch between two currents flowing through phase and neutral detect by RCD and trip the circuit within 30Miliseconed.
The most widely used are 30 mA (milliamp) and 100 mA devices. A current flow of 30 mA (or 0.03 amps) is sufficiently small that it makes it very difficult to receive a dangerous shock. Even 100 mA is a relatively small figure when compared to the current that may flow in an earth fault without such protection (hundred of amps)
30mA is the maximum value permissible for personal shock protection and 300mA is the maximum value permissible for fire protection
0 Comments