RCD wiring?

[spudgun]

i've just bought an old house with a "heat as u go" type shower it works fine untill u look at the wiring all its got for protection is a 30 amp re wirable fuse!!! so i've got my 4mm twin isolation switch and MCB the only thing thats baffling me is the rcd. Off i go to the B n Q superstore where i find a 63amp 30ma 2p rcd for use on electric showers, 50 quid so i got it its been opened and no instructions so how do i wire it up its got 4 connections and mounted in a plastic case bit confused and everyone i know that will know the answers have all gone to spain ?? Please help cos till i know i ain't gettin in the shower (the mrs will be ok though right)

 

[breezer]

one side is in the other side is........

 

[spudgun]

...out but what you do with the earth??? its a plastic case? or am i stupid?

 

[alexnic]

There should be a brass terminal fixed inside the case, the earth should be connected to that. As you said it's a plastic case so it cannot be earthed, the terminal is to ensure continuity of the earth from the supply to the shower

 

[spudgun]

This is what confused me there is no terminal in the plastic box or anywhere on the rcd but im right in saying the earth doesnt go through the rcd just round. (the mrs is still useing shower)

 

[breezer]

yes it does "go round it"