Basic rewire of older house

[Joinaman]

Hi there

am thinking of updating grandmas house ellectrics

 was thinking of fitting new 6 way board, with earth rod

All cables to be 3 core , twin and earth 

new electric shower 

Any reason why i cannot wire as uk style. 

Ring main for sockets and loop system for lighting ?

4mm cable for the shower, maybe a 6kw shower ? Cable run approx 25m

would the earth back to the board be sufficient from the shower, or would I have to have an earth rod for this too

16amp breakers for lighting and 32 amp for sockets

32 amp for shower ok or would I need larger ?

its a simple house, 2 rooms , plus outside toilet/shower and outside lighting

was thinking of separate cuircuits for the inside and for the outside sockets and lights, plus circuit for shower with one spare 

house design means it will never have air con fitted, nor fancy kitchens, hobs , cookers or things

thanks for any advice

[bankruatsteve]

Absolutely do not use rings.  

 

20 amp with 2.5mm2 cable is the "standard" for sockets.

 

NO RINGS.

[Joinaman]

No rings ?

any reason why not

much safer than doing radial circuits ?

whats the regs here for the total sockets on one radial circuit ?

i thought it would be much easier just to run a ring circuit rather than separate circuits ?

 

[Joinaman]

2.5 twin cable ?

why not use 2.5 - 3 core cable, surely this would be much safer, 

why install sockets with no earth ?

 

[bankruatsteve]

9 minutes ago, Joinaman said:

2.5 twin cable ?

why not use 2.5 - 3 core cable, surely this would be much safer, 

why install sockets with no earth ?

Earth should be on all sockets.  Use 3-core if you can find it but most installations will just run ground as a single along with 2-core.

 

Oh - the '2' stands for "squared" not 2-core.  

Edited December 19, 2017 by bankruatsteve

[bankruatsteve]

13 minutes ago, Joinaman said:

No rings ?

any reason why not

much safer than doing radial circuits ?

whats the regs here for the total sockets on one radial circuit ?

i thought it would be much easier just to run a ring circuit rather than separate circuits ?

 

The "safer" claim is not valid.  But, Crossy is a Brit and will explain better when he comes on.

[Crossy]

2 hours ago, Joinaman said:

No rings ?

any reason why not

much safer than doing radial circuits ?

whats the regs here for the total sockets on one radial circuit ?

i thought it would be much easier just to run a ring circuit rather than separate circuits ?

 

NO NO NO!!!!

 

No rings, period. Thai plugs do not have fuses, so if you put in a ring with a 32A breaker that's what is protecting the bit of speaker cable on your fan. The 16A rated plug won't be too happy either. Recipe for a fire.

 

Rings are not safer than radials, indeed they are going out of fashion in the UK mostly due to the difficulty of testing that they really are still rings. There's a significant fire hazard from a broken ring.

 

There is no limit to how many outlets you can put on a radial, so long as the breaker is appropriate for the cable (20A on 2.5mm2). Run two radials to the kitchen and get 40A worth of juice instead of 32A.

 

6A and 1.5mm2 for lighting.

 

32A and 4mm2 for your water heater unless you want to go over 7kW

 

Thailand is TNC-S with MEN, so you'll have a rod anyway.

 

RCD / RCBOs are essential, particularly on your water heater, outside lighting / outlets and your pool.

 

 

 

 

[Joinaman]

Thanks Crossy

i heard about the going back to radials in uk, but understood there was a limit on the amount of outlets, plus minimum cable size of 4mm ?

so will go as you say, , 3 radials of about 6 outlets on each

 2 lighting circuits , one inside, one outside, maybe 4 lights on each

with separate circuit for shower

can I still loop the lighting ? 

In this house, the sparks ?  has got wires twisted together like spaghetti junction up in the roof void, would be nice not to have that again

but still use earth rod for shower, rather than the earth wire back to board ?

shower will be 6 kw I think, not seen bigger here

[bankruatsteve]

As Crossy states, there isn't limit per se for radial sockets.  The US code requires a socket every 2 meters of horizontal wall space minimum.  My rule of thumb is a socket anywhere someone might want to plug something in and especially to avoid any need for an extension.  I also like to put two duplex sockets where the TV/entertainment is and where computer stuff will be.

 

If "looping" means a ring connection back to the CU, then NO.  Loop all you want otherwise.

 

I'm guilty of letting wires go where they will in the attic area but it shouldn't look like spaghetti.  Running in conduit is the proper method.

 

There is no reason I am aware to have a separate earth rod for the shower.  All ground wires would ideally go back to the CU and from there to a ground rod.

 

Edited December 19, 2017 by bankruatsteve

[Joinaman]

Thats why  i thought of using ring circuit like in UK

so i could put plenty of sockets in the house

I hate using extension leads especially when the house has been rewired, there should be no need if thought is given as to where to put outlets

for the price of a socket and a bit of cable its crazy not to put extra in while doing the work

In today's way of life, i think there is no such thing as too many sockets, 

at the moment her uncle and grandmother have only 2 sockets in the house , and loads of extension leads, with most wiring in bell wire type

Lighting is so bad they have torches to find things after dark 

[Crossy]

Rings are unknown outside the UK. Even places that use BS 1363 outlets such as Malaysia, Singapore, Hong Kong wire radials.

 

Just run radials in 2.5mm² on a 20A breaker, no limit on the number of outlets, most will be less than an Amp or two anyway.

 

 

[Joinaman]

thanks Crossy, will do

suppose its not like the uk where people can plug nin lots of 3KW heaters and things

[Joinaman]

Just had new board fitted by a local sparks

curious about the earth wire

i would have thought e tthe wire would have gone to the earth bar above to earth the metal board 

he has made the bar neutral with the other bar eart

is this ok ?

seems odd but this is thailand !

[RichCor]

As Crossy previously posted, Thailand uses TNC-S with MEN (Multiple Earthed Neutral) in most locations so a 'bridge' wire permanently connects Neutral to Earth Ground bus bars and both connection bars are technically at the same potential ... so the Ground Rod wire can go on either.

 

I see from your pics that they've reversed the colors on Live/Neutral. 

Just ran into yet another install today where the wiring is 'white' as Live, but then utilizes 'black' (now the Neutral) through all the light switches. Drives me nuts.

[Crossy]

Slightly unconventional, but there is a MEN link in place.

 

Your rod should go to the ground bar with all the green/yellow wires.

 

Your blue (correct colour) neutral from the main switch to the neutral bar looks a tad thin, with that 63A breaker you should have a minimum of 10mm².

 

EDIT I just noticed that your incoming breaker appears to be an RCD rather than an RCBO so you have NO over-current protection on your incoming supply. This is a serious issue unless there's an over-current protective device upstream of the board that we cannot see.

 

[Joinaman]

thanks Crossy

Thought it was a bit odd to put the earth wire in there, but if it works, then ok

the top earth bar is earth with external rod and decent earth wire

RCBO ??

only have what is seen, nothing else is on the incoming mains

thought the RCD was ok for safety, never thought about anything for overcurrent

So should the RCD that is in now, be changed for a RCBO ?