Incoming TT supply

[barch]

I've just moved into a 1950's built house. It has lovely bakerlite black fittings on the wall and a fuse box that is just plain old. The supply comes into the house on an overhead cable and the Electrical Supplier does not provide an earth so I have an earth rod. Which I believe is a TT system.

I'm going to replace the fusebox with a new consumer unit. Now my question is, should I just put in new CU with MCB's or should I look to put RCD's on all the circuits? I'm worried that the whole CU will trip with this set up. Do I need a main time delayed RCD in the CU?

thanks

Ian

 

[securespark]

My solution would be to ask the DNO (via the company you pay to provide your electricity) to PME the supply. That way, you do away with rods & variable loop readings, and you don't need a time delay RCD.

Assuming you PME the supply, fit a split-load board if you are not rich, or, if super-rich like John ( ), use RCBO's. These are a much better solution, but are more expensive.

 

[barch]

I'll try that, thanks. I've had two Southern Electric guys out and neither ave suggested this. They can still PME it even though its coming in on the overhead?
Ian

 

[BJS_Spark]

And of course you will go through all the testing and inspection required by BS7671. You are aware of part p also I assume?

 

[RF Lighting]

I've just moved into a 1950's built house. It has lovely bakerlite black fittings on the wall and a fuse box that is just plain old.

Sorry, but that screams at me that your wiring may be waaaay overdue for replacement.

I suggest you get someone to make sure for certain that the origonal wiring is not still in service.

They can still PME it even though its coming in on the overhead?

Normally yes, but only the DNO can answer that for your specific supply.

 

[CAWORK]

Barch, just out of interest, could you tell me if the socket outlets are the 13 amp flat hole type (as used today) and wired in a ring circuit, possibly rubber sheathed cable etc?

Is it possible to give some pictures?

 

[JohnD]

We like pictures

 

[systemtek]

Just curious what/if do the supplier charge to PME a supply ?

 

[marcusone]

Our local supplier charges about £60.00. Definately worth going for if you can get it.

 

[securespark]

The old MEB and United Utilities charge around 100 quids.

 

[barch]

Hi, everyone, I'll get some pics of the wiring in here for you all as it is, at best, hairy. For instance, the cable that feeds the garage is a flex extension which is fed from a socket in the loft. This one socket also feeds a skt in the kitchen. The power went off on the washing machine, and it was only tracing the cbale back that I found this odd socket mounted in the loft. There are countless other examples. I'll get pics.

Yes, I'm aware of part P. I'm intending doing most of the work myself, but getting someone in whos qualified to connect it all up. I'm moving the fusebox and meter anyway. Southern have quoted £360 to resite the meter and they said that I could have the cable buried, if I dig the trench. At no time did they say, "really should PME this"!! I will call thm on Monday to ask them to quote.

I'll take some pics this weekend.

 

[barch]

Hi, Before I contact the Electricity company, Can they provide a PME supply from the current supply? The overhaead needs to sta because there are so many land drains around here that I cant dig the required 450mm down so they can bury the cable.
cheers

 

[barch]

Hi, Before I contact the Electricity company, Can they provide a PME supply from the current supply? The overhaead needs to sta because there are so many land drains around here that I cant dig the required 450mm down so they can bury the cable.
cheers

 

[Steve]

These days, PME can usually be provided from an overhead supply, but ask first. We dont know.