Advice, if any on installing a shower please.

[Newinthegame]

Hi there Guys,
I got good feedback on my last post and being a newbie sparks wanted some guidance on this one please.
Customer requires a new shower to be fitted. 10.5KW
There is an existing 6mm t+e in the loft, but i am going to upgrade this to 10mm and connect into the contactum DB....rcd side via a 50 amp breaker.
The main supply to the DB is a 16mm t+e which comes from a very old MEM switchfuse which has....i think a 60a fusewire attached.
Would it be wise to change this switch to a 80/100 amp isolator. RCD aswell because it is TT system. Concerned that this may blow under the extra load!!!
Does this sound ok? Any advice would be great.

 

[Top Cat]

If cant quite work out if the Contactum DB is what you are fitting or the original?

If it is original you don't need the old MEM switch fuse, just upgrade tails and earthing if required.

If it not original, 25mm tails into Henley block and split tails into MEM switch fuse and new Contactum DB.

 

[Newinthegame]

The contactum DB is the original DB in the house which is on the first floor.
The incoming supply(T-T) comes into a seperate outbuilding about 4/5 metres from the contactum DB. The outbuilding is where the MEM switchfuse is and it is this that supplies the DB via a 16mm T+E. My concern is that with the additional load from the shower the fuse may blow because i think it is rated at 60 amp. Do i change the switchfuse because of the distance to the DB? And its T-T so it should now be an RCD?

 

[Guest55]

The contactum DB is the original DB in the house which is on the first floor.
The incoming supply(T-T) comes into a seperate outbuilding about 4/5 metres from the contactum DB. The outbuilding is where the MEM switchfuse is and it is this that supplies the DB via a 16mm T+E. My concern is that with the additional load from the shower the fuse may blow because i think it is rated at 60 amp. Do i change the switchfuse because of the distance to the DB? NO

And its T-T so it should now be an RCD? YES

What other loads / circuits are on the house DB ?

 

[Newinthegame]

Standard stuff. 1 x cooker, 1 x ring main, 2 x lighting, 2 x radials, 1 x CH boiler.
Gettin a bit confused though. Dont wanna run the risk of leaving in the mem switchfuse and the fuse blows when the shower is on. Then there would be no supply to the DB. So if i change it then i must replace with a DP RCD 80a 30Ma?? this way it then protects the 16mm t+e going to the DB right?

 

[Guest55]

The problem isnt whether to replace the MEM fuse for a bigger one , but whether the 16mm T&E submains to the house is upto the job of suppyling extra loads.
Unfortunatley i'd say not when you consider the existing circuits already in use.

How is the submains installed ?
clipped direct , buried in ground , in conduit , suspended overhead ?

 

[telectrix]

So if i change it then i must replace with a DP RCD 80a 30Ma??

tails would only require RCD protection if buried <50mm deep in walls.

 

[Moses]

What is the rating of the fuse at the supply head ?