Hi was hoping someone could help - I'm sorting out my decking area and the previous owner has installed an external 2 gang socket that is mounted on a fence with some thick (10mm i think) armoured cable running into it. I took it off the fence ( as that part of the fence needed mending) and reinstalling it and have noticed there is no earth lead running from the faceplate to the back box. So there's a Live, neutral and earth all running to their corresponding blocks within the faceplate, but the backbox has it's own block for the earth. On the rare occassion I've done this inside, I would introduce a new connecting piece of wire in it's own earth sleeve to connect both earth blocks, but in this case the box is plastic. So my questions are: 1) Should I change it or is it okay as it is? and 2) How does earthing a backbox work when it's plastic? Thanks so much!