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Stephen Fasham
 
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Default 2 wire circuit - no earth

I have two supplies to my house(s) which is not the problem here, but
does crop up as a side issue. I am planning to get the two combined
and initially intend to use a henley block to divide after an RCD
incomer (100mA time delay as TT installation) to the left hand house
dis. board and the collection of switch fuse units on the RHS. This
weekend I was trying to finally identify what does what to prepare for
combination.

First problem was that the LHS dis board appeared to be wired on a
live-neutral reverse. Removing the top of the henley block and dis
board confirmed that red went to the neutral bar, and black to the
busbar. Feeling that this qualified as in need of an urgent fix I
removed the company fuse and corrected the wiring to the incomer. The
rest of this side seem OK-ish although I need a couple of 30amp
Junction boxes to replace the insulation taped connector block on one
socket ring.

On to the LHS.

All the circuits are wired on individual switch fuses most of which
seemed OK although identifying which sockets were on which circuit was
challenging (front and back wall of the kitchen on different
circuits!). There is a minor issue of a hall light which has been
tailed into the door bell using connector block so this will be tidied
up.

The final problem is that there is one circuit which is ancient and
has no earth, fuses in the live and neutral. This feeds the downstairs
lights + a couple of upstairs lights + 1 downstairs socket and 1
upstairs sockets. I don't want to replace it ahead of re-wiring in
general so want to make it as safe as possible pending that. For the
lights, most of the switches are bakelite rocker switches which have
no earth connection so are no more dangerous now than they have ever
been. Where I am wondering what to do is over newer switches where the
2 core has been replaced with T&E so there is a floating earth which
picks up a high induced voltage but worse has no path to ground in the
case of a live-earth fault at the switch. Is the best thing to replace
the switches with pull-cord ones for the moment and if I don't should
I disconnect the floating earth?
For the sockets I would take them out but they are the two hoover
points. The hoover is double insulated so less worrying but if they
are there the tendency to plug other stuff in is almost inevitable. As
an interim measure is it a good idea to connect the earth points in
the sockets to earth in another circuit using a separate earth wire or
is this somehow worse.

Please no posts saying pull it out and start again, because I am, but
not tomorrow. Any advice on how to improve the situation in the short
term very gratefully received.
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Christian McArdle
 
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Default

if I don't should I disconnect the floating earth?

Probably.

For the sockets I would take them out but they are the two hoover
points.


Disconnect the sockets. Use a suitable extension reel into a different
socket.

All this assumes, as you state, that a proper rewiring is imminent anyway.
Make sure the lighting circuit is on a 6A MCB or 5A fuse. The shameful
bodger who put the sockets on the circuit may have upped the fuse rating to
"wire" standard when the cleaner tripped the fuse.

Christian.


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mrcheerful
 
Posts: n/a
Default


"Stephen Fasham" wrote in message
om...
I have two supplies to my house(s) which is not the problem here, but
does crop up as a side issue. I am planning to get the two combined
and initially intend to use a henley block to divide after an RCD
incomer (100mA time delay as TT installation) to the left hand house
dis. board and the collection of switch fuse units on the RHS. This
weekend I was trying to finally identify what does what to prepare for
combination.

First problem was that the LHS dis board appeared to be wired on a
live-neutral reverse. Removing the top of the henley block and dis
board confirmed that red went to the neutral bar, and black to the
busbar. Feeling that this qualified as in need of an urgent fix I
removed the company fuse and corrected the wiring to the incomer. The
rest of this side seem OK-ish although I need a couple of 30amp
Junction boxes to replace the insulation taped connector block on one
socket ring.

On to the LHS.

All the circuits are wired on individual switch fuses most of which
seemed OK although identifying which sockets were on which circuit was
challenging (front and back wall of the kitchen on different
circuits!). There is a minor issue of a hall light which has been
tailed into the door bell using connector block so this will be tidied
up.

The final problem is that there is one circuit which is ancient and
has no earth, fuses in the live and neutral. This feeds the downstairs
lights + a couple of upstairs lights + 1 downstairs socket and 1
upstairs sockets. I don't want to replace it ahead of re-wiring in
general so want to make it as safe as possible pending that. For the
lights, most of the switches are bakelite rocker switches which have
no earth connection so are no more dangerous now than they have ever
been. Where I am wondering what to do is over newer switches where the
2 core has been replaced with T&E so there is a floating earth which
picks up a high induced voltage but worse has no path to ground in the
case of a live-earth fault at the switch. Is the best thing to replace
the switches with pull-cord ones for the moment and if I don't should
I disconnect the floating earth?
For the sockets I would take them out but they are the two hoover
points. The hoover is double insulated so less worrying but if they
are there the tendency to plug other stuff in is almost inevitable. As
an interim measure is it a good idea to connect the earth points in
the sockets to earth in another circuit using a separate earth wire or
is this somehow worse.

Please no posts saying pull it out and start again, because I am, but
not tomorrow. Any advice on how to improve the situation in the short
term very gratefully received.


do not assume that two adjacent properties are on the same phase.

mrcheerful


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Christian McArdle
 
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Default

Generally, properties will be on different phases to those next door.
Check both circuits are on the same phase before going any further!


Why is this an issue? The two houses will be very shortly on one phase, if
they're going to be connected from a Henley block from one of the original
supplies.

Christian.


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