Help With Shower Pull Switch

[Papalzru]

Hi, I`m a DIY wannabe and I`m trying to learn as much as I can.

I am currently installing a shower in my bathroom. The pull switch/cord was already fitted in the house Ive recently moved in to, so the electric from the main circuit box is already installed.

All I`m doing is connecting the shower to the pull switch. I connected the shower up, pretty basic, connecting the positive to the positive, the negative to the negative and the earth to the earth. Now I have opened the pull switch box. I know to connect the blue to the blue and brown to brown like in the shower itself. The thing that is confusing me is the earth wire. The wire from the main circuit box has an earth connected to the pull switch and then their is another earth wire on its own which goes up into the attic as well. I have no idea where it comes from.

My questions are,

What is the 2nd earth wire likely to be connected to?

Also, do I need to do this with the wire from the shower? I will obviously connect the earth to the socket on the opposite side but do i need another earth wire coming from that socket and going wherever the other wire disappears to?

I hope Ive explained myself well enough.

Thanks to anyone who can help me.

Cheers

P.S I have a pic but it wont let me attach the link until ive made 10 posts.

 

[ProDave]

Second earth wire was a cross bonding earth wire that was installed to strap the earths of everything in the bathroom together. So leave this in place and connect the shower cable earth into whichever terminal it will fit into.

By the way it's Live and Neutral not positive and negative.

And you have checked the size of the existing cable and the rating of it's mcb to ensure both are adequate for the rating of the new shower? 

 

[Nicky Tesla]

Make sure your not in the shower while you are doing this.

 

[Papalzru]

Second earth wire was a cross bonding earth wire that was installed to strap the earths of everything in the bathroom together. So leave this in place and connect the shower cable earth into whichever terminal it will fit into.

By the way it's Live and Neutral not positive and negative.

And you have checked the size of the existing cable and the rating of it's mcb to ensure both are adequate for the rating of the new shower? 

Sorry I meant L and N, confused myself.

The shower is 9.5kw and the cable fitted already is 10mm so I am also using 10mm.

How do I check the mcb?

cheers

 

[steptoe]

Is there an RCD fitted,

and are MEBs up to scratch?

 

[Papalzru]

Is there an RCD fitted,

and are MEBs up to scratch?

Yes their is an RCD fitted.

What does MEBs stand for?

 

[Marvo]

Equipotential bonding.

http://talk.electricianforum.co.uk/topic/4616-supplementary-bonding-in-bathrooms/

There might have been changes in the regs since this discussion took place.

 

[SLIPSHOD & SLAPDASH]

Really, really make sure all the terminations are tight. Dont use a piddly little driver, but  also dont use a huge big one that will sheer off the screw heads. Many fires/overheating are caused by shower connections.

 

[kerching]

Consider using a crabtree pull switch......they are the best bar NONE, end of!

Just saying

 

[Papalzru]

All done.

Thanks for the help from Pro dave. Kept his advice nice and simple.

cheers