A residual-current device (RCD), residual-current circuit breaker (RCCB) or ground fault circuit interrupter (GFCI) is a device that quickly breaks an electrical circuit to prevent shock.
RCDs are a needed part of health and safety, and the building regulations insist upon their use.
There are exceptions to having RCDs, and these include circuits that do not feed portable equipment outside the installation. (e.g., lighting in fixed positions, immersion heaters and storage heaters where water penetration is not likely.) Also excluded are fire alarms, lifts and medical equipment, etc., where loss of mains power would create more danger than the electrical shock itself. A general rule-of-thumb to assist identification would be that any circuit protected by an RCD is considered ‘portable’. i.e., extension cables to portable tools; table lamps.
Note that with new installations, sockets that power garden pumps must not only be RCD-protected, but they must also be connected via a special weatherproof socket which incorporates its own built-in 30mA RCD ability. Weatherproof socket outlets with individual RCD’s are available, and these can easily replace the 13amp weatherproof outlet on your present pump, but note this is not a requirement for replacement unless you decide to change your socket. For an Electrician Gloucester, visit https://www.dpalmerelectrical.co.uk/electrician-near-me/electrician-gloucester/
An installation using an RCD generally includes a split-consumer unit. One busbar, on the right-hand side when viewed from the front, takes the switched live feeds from the RCD. All socket outlets, the shower, some fixed appliances, etc., will connect here. The other busbar provides connections to fixed appliances like lights and immersion heaters, and to cooker units, etc.