Masterplug 13A Fused Plug-Through Active RCD Adaptor (63731)

Hi AndyTut, As the invertor will be outputting 220-254V AC at 50Hz (we presume) there shouldn't be any issue with using it to feed the RCD adaptor.

Hi PaulKruger, With any moving-blade device there is always a small chance of it cutting through it's own power cable, an RCD is the device which will react to such an event and cut the power off before it causes any major harm so would be a good idea to use.

Hi MGomez, Your WP22 outdoor double socket is designed for use with standard sized UK plugs so this adaptor will barely fit into it with the lid open, let alone with it closed and sealed against fluid ingress. You may be better off considering an in-line RCD to be wired into the hot-tub cable a little way away from the plug and socket interface (but ScrewFix don't appear to stock any of these, so you would need to try somewhere else for one).

Hi StevePB, It doesn't actually matter what device is connected to the output (protected) side of an RCD, it will continue to operate as designed, i.e. it will trip if there is an imbalance of greater than 30mA between the Live and Neutral power consumptions for long enough (measured in milliseconds). RCDs have no intrinsic heat protection characteristics, and will only see a short if it is to Earth (Live to Neutral shorts will tend to draw large currents instantaneously so would blow a fuse or trip an MCB rather than triggering an RCD).

Hi Joe8Rory, As this is an Active device it will trip whenever the supplied power to it is lost, meaning it would require physically resetting once the power comes back again, so if you were going to use it with a remotely activated adaptor then the RCD would best be in the wall socket before the other adaptor to avoid this need for being reset constantly.