There are two types of technology a

There are two types of technology available in residual current devices, electromagnetic & electronic and both offer very reliable performance. Electromagnetic devices use a very sensitive torroidwhich operates the trip relay when it detects very small residual currents. These devices generally require no reference earth lead and are unaffected by temporary loss of supply, as the power to trip the device is derived directly from the fault current. Electronic devices do not need such a sensitive torroid as electronic circuits within the device amplify the signal to operate the trip relay

Hasil (Bahasa Indonesia) 1:

There are two types of technology available in the residual current devices, electromagnetic and electronic and both offer highly reliable performance. The use of electromagnetic devices are very sensitive torroidwhich trip relay operates when it detects a very small residual current. These devices generally require no reference earth lead and is not affected by the temporary loss of supply, as the power to drive the device comes directly from the current error. Electronic devices do not need to be as sensitive as torroid electronic circuit amplifies signals within the device to operate the relay trip

Hasil (Bahasa Indonesia) 2:

There are two types of technology available in residual current devices, electromagnetic and electronic and both offer very reliable performance. Electromagnetic devices use a very sensitive torroidwhich the trip relay operates when it detects very small residual currents. Generally these devices require no reference earth leads and are unaffected by the temporary loss of supply, as the power to trip the device is derived directly from the fault current. Electronic devices do not need such a sensitive torroid as electronic circuits within the device amplify the signal-to-operate relay trip