You may RCD at the socket, if you wish to and if the wiring from the main board to that point does not need an RCD - SWA or singles in steel conduit would not for example. It could be the local isolation.
You may RCD at the socket, if you wish to and if the wiring from the main board to that point does not need an RCD - SWA or singles in steel conduit would not for example. It could be the local isolation.