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(jim_in_sussex) wrote in message . com...
wrote in message

Question 1. I have been examining my earth bonding and have found
that the earth connection between where the cable enters my house to
the other size of the main fuse is made from earth cable that is only
about 3mm thick at most and it is not insulated. Presumeably this is
fairly old. This is only a short length about 25cm. There is then a
copper covered cable that goes for about 6 metres to the meter. The
earth connection into the consumer unit and connected to the gas and
water is much more substantial and is insulated.

From your bare description this sounds inadequate but for me to make
useful observations you need to provide clearer information about your
installation eg

approx age; if possible the earthing system (TT/TN-C-S/PME/TN-C are
the most likely).

The earthing is TNS. i.e. supplied via the armoured cable coming in
from the street. This looks to be at least 30 years old.

This goes into the suppliers fusebox. The other side of the fusebox is
a a copper covered cable which goes to the meter.

The armoured cable and this copper covered cable are joined on the
outside to continue the earth. This is done with uncovered stranded
cable of about 3mm diameter.

--- -------------
============= Fuse ================ ------- to meter
---| |-------------
|----earth link-----|

From the meter the tails are connected to the consumer unit. The earth
connection into the consumer unit is 10mm diameter insulated cable.
The earth is then connected to the gas and water pipes, again using
10mm insulated cable.

As far as I can tell this part appears to be fairly modern and appears
to be in line with my understanding of the regualations. It just seems
strange that the incoming earth by the fuse seems so inadequate.

Where does the supply companies responsibility end, is it at the fuse
or the meter. If at the meter, then I will be getting the electricity
company in to replace this.

A 'schematic' of your installation would help. eg something like

incoming mains - supplier's fuse - supply meter - main switch -
consumer unit (or fuse box) -house circuits

& any other boxes, indicating where the earth connects in & the
connection to your water/gas/oil pipes. Any indication of cable sizes
you can give would also help. Is there an earthing rod?

Much of the information (with diagrams) you want is in the IEE On-Site
Guide (checkout amazon &/or the IEE web site to purchase)

Is there any danger posed by the thin link around the main fuse? Should
I replace it?

If you can repost with above info will try to help.

Question 2. (see previous post) In my laundry/shower/toilet room there
is no earth bonding. I understand that I must link all the pipes
together.

that's right (see on-site guide)

However my radiator is on the otherside of the room and I
don't want to rip up floor boards to fit the cable. Is it alright to
route this via my cellar back to where the cold water pipe enters the
room. This means that effectively the cable will be going around the
outside of the room. Do I have to put the connection in the laundry
room or can I make this in the cellar?

SFAIUI the bonding cable does not have to be within the room, though
the clamp links to the metalwork do. Caution & ohms law suggest
Prudence would keep the cable route as short as possible. It must also
connect to the main house earth bonding (into the earth in a
convenient socket seems to be OK SFAIUI).

also from your other post

....further question. I am installing additional sockets in my
kitchen.
As this is being replastered I intend to cover the cables with
capping/sheathing. If I use the galvanised type should this be
earthed?

FT&E PVC cable does not have to be covered with capping before
plastering. It can be clipped to the wall and simply plastered over
with the browning (undercoat) coat.

Capping (especially metal) provides some resistance to drawing pins
and the like but isn't foolproof. Don't confuse it with conduit which
usually comes in thick, nail resistant, tubes & is a diffeent kettle
of fish (with different cable rating tables applying).

Capping does not need earthing. Conduit may do.

You may only route cable in 150mm wide bands, vertically and
horizontally from a fitting (a switch, socket, light outlet etc) &
along vertical wall corners and the ceiling/top of wall corner. Note
routeing behind skirting boards doesn't normally meet these rules. If
you depart from these routes (eg run diagonally across the wall) then
the cable must be at least 50mm deep in the wall or run in earthed
conduit (not capping). Again, rules are in the on-site guide.

BTW what do you mean when you refer to 'sheathing'? The grey
(sometimes white) covering of FT&E cable is a sheath intended to
protect the red & black insulation covering the copper cores from
physical damage. If your reference to sheathing means you are not
intending to use FT&E cable but individual L, N & E cables then they
must be run in conduit. SFAIUI covering individual cables with
capping is insufficient protection.

By sheathing I was referring to the capping. Thanks for the answer.

HTH