Incoming meter tails, and jnc box

[MasterAbacus]

Hi all,

Ive just been looking at our incoming electrics, and noticed this set up..

Incoming supply goes to a junction box which branches off, with tails to the the main CU then the feed down the garden to the garage which is on its own CU.

My dilema is that the main CU is a standard one, and as we have a new shower and wanted protection, is there anything wrong with splitting the tials again prior to them entering the main CU so i can put a seperate single box CU for the shower protection?

 

[bernardgreen]

Incoming supply goes to a junction box which branches off, with tails to the the main CU then the feed down the garden to the garage which is on its own CU.

Is there any fuse between supply and the feed down the garden to protect the cable if damaged ?

My dilema is that the main CU is a standard one, and as we have a new shower and wanted protection, is there anything wrong with splitting the tials again prior to them entering the main CU so i can put a seperate single box CU for the shower protection?

Best to have the block changed to have the right number of terminals for the number of tails.

 

[MasterAbacus]

Doesnt seem to be a fuse for the garage supply...

obvs the 100amp fuse in the supply, the tails out to splitter... nothing else.


From what you are saying is im better puttin in new tails from that junct box? ie instead of the supply splitting in two ways, it splits in three???

Existing to CU
Existing the Garage CU
NEW to Shower protection???

 

[bernardgreen]

Doesnt seem to be a fuse for the garage supply...

obvs the 100amp fuse in the supply, the tails out to splitter... nothing else.

Will the cable stand 100 amps in the event of a short ciruit. ( more than 25 kilowatts until the incoming fuse melts )

The feed to the garage should be taken from the CU via a suitable rated MCB

From what you are saying is im better puttin in new tails from that junct box? ie instead of the supply splitting in two ways, it splits in three???
Existing to CU
Existing the Garage CU
NEW to Shower protection???

YES but it would be better to have the garage from a CU

So why not put a second CU with two MCBs One for the shower and one for the garage

 

[MasterAbacus]

For me to connect the Garage to the Main CU then i would need to extend the Cable as its cut off in the Meter box... and dont really want to do this.

Ive spoken with niegbours who have the same setup and all are done this way from new 18 years ago....apparently...

The Earth wire on the Garage feed isnt even connected in the Suply box, its just left bear and un connected, as there is a seperate earth wire in the Garage that seems to disapear in the ground... Im assuming, and (Hopefull) this goes down to an earth rod.... Guess ill have to dig and find out about that bit.

Ive plenty of room in my new main CU to fit half a dozen more MCB`s in, but as its not split load i was thinking of having the shower with rcbo ? protection in stead of runnin git of a 40Amp Mcb as it currently setup.

 

[JohnD]

RCBO is a great choice

But your existing installation sounds unsatisfactory. If you can lay your hands on a digital camera and put up some pics of the cables around the meter, connector block and CU, we'll doubtless have more wisdom for you.

We particularly want to see if there is an earth connector or cable coming out of the side of the supply head, and if there is a label saying "Protective multiple Earth" near the meter.

"we like pictures"

 

[MasterAbacus]

Picture of my Meter box.... (Bloody cold outside you know)....

I hope this works, and helps.....

 

[jj4091]

http://www.toolstation.com/shop/Electrical/CableManagement/d190/sd2460 i think this is what you need to look at ( connecting blocks item 32184)

 

[luminaire]

Ive plenty of room in my new main CU to fit half a dozen more MCB`s in, but as its not split load i was thinking of having the shower with rcbo ? protection in stead of runnin git of a 40Amp Mcb as it currently setup.

Your best bet for the shower is as you say have an RCBO. That solves that little problem.

Our main concern here is your garage arrangements. As it stands it would not pass an inspection and need drastic action to alter it.

It has alresady been suggested that too should come off your CU and be RCD protected - another RCBO if you like.(SP rated up to 50A).
Might be cheaper in the long run to either convert to split-load or buy one!

It would then feed your garage using SWA cable underground.

 

[JohnD]

If the garage has a small CU with an RCD, then it is not necessary to have another RCD at the supply end. It is probably more convenient to have the RCD near the point of use. However, it is essential to have the garage cable protected by a switchfuse or other means at its supply end. This would not be difficult but you would need an electrician in (or perhaps your supplier) to make the connection as the existing block is unswitched and permanently live.

The sheathing on the tails is clumsily done too.

The cable earth should be G&Y sheathed and connected though I'm not clear what the earthing arrangement is. How far is the garage from the house?

Give us a picture of your CU and tell us the brand/type on the devices inside it, please.

 

[MasterAbacus]

the garage is about 15 - 20 meters away from the Incoming mains, has its own small CU with Main switch and 4 Mcb`s 2x 6a for lighting and 2x32a for mains (two circuits one light and ring in gargage, and 1 ring and light in adjoining shed.

the Main CU in the house is just standard CU only about a year old.
fitted with 2 x32, 2 x6, 1x45,, 2x16. Mcb`s. theres room for another 6 Mcb`s if needed.... i guess ill use these when extend house later in the year.