Learned Friends,

I need to get my house rewired, completely. It's got an old style radial system where spurs fan out from the fuse box, much like spokes of a bicycle from the hub. Some of these have been extended (naughty, naughty) by the previous owner and I want to rip it all up and make it good, up to date, safe and, incidentally, have a dedicated hi-fi supply/maybe CU fitted.

I am, of course, going to use an NIC/EIC qualified contractor for the job.

Given the nature of this topic, please don't anyone mention various modifications/short-cuts/random naughtiness that may cause our gracious hosts to kill the thread.

I have a few questions for those in the know:

*as I'm having the whole shebang redone, is there any need to have two CUs, one for the rest of the house and one for the hi-fi?

* does anyone have experience of the plaited 'Kimber' style cable as sold for mains installations by Russ Andrews? I may blow for this but only if its worth it.

* what are your thoughts on whether an electrician is likely to be happy to install heavy grade (10mm2) cable to the hi-fi area/sockets.

* is it allowable to have conections run uninterrupted directly from the CU to the back of each hi-fi box, terminated just in a hefty IEC plug? Thus there would be no sockets (round pin or otherwise) between the CU and each component. The units would be protected by their own *completely standard* fuses and the protection provided by the CU.

*are there different (legal/sanctioned) types of trips for the CU, such that I could advise/ask the electrician for the lowest impedance ones.

* Earthing - my house has a rubbish earthing system and the metal gas pipes in the road outside were recently replaced with plastic ones - should I compound my internal disarray by proposing we dig up my patio and connect to a dirty great earth rod buried in the front garden?

* I'm wary of using other people for doing decent quality jobs - any good questions I can ask my sparky to determine whether he's a loony or top-notch? I don't mind paying for kwality (hence I use Naim kit) but I don't want to be ripped off by stupid hourly rates or barely adequate work.

*my meter is an old style 'spinning horizontal disc' type - I imagine the advice from the electrician will be to get the power company to change it to a modern digital one. Are these low-impedance/do they inject any noise onto the mains?

*is there anything else I should ask about?

*oh, and do you like the idea of lights inset in the wall up the side of the stairs, say, every third step, or is that just showing off?

What thinks thou? Any tame electricians out there want to give me a few tips?

Best,

Richard.

quote:

oh, and do you like the idea of lights inset in the wall up the side of the stairs

You've been watching too many house make-over programs.

Allan

Allan,

Arf!

I ask because I saw one (just one) make-over program where a guy was selling a flat he'd equipped with lights up the stairs. A female prospective buyer was filmed walking up the stairs.
'Look at this! Lights up the stairs!' she said [pause] 'How completely pointless'.

Cheers!

Rich.

For the stair lighting you want LED technology.

check out mr-resistor.co.uk for led lighting.

As usual its not cheap but because it only uses 1 watt per light its a very safe method, my whole kitchen has 14 lights with 14 watts of electric being used.

Depending where in the world you are, you might discern no difference sonically. Or you might. I never have, in 2 Bristol UK properties.

My advice is to have it done using via any reasonable quote-recommended 'specialist' (keeping it as simple/cheap as possible) you can access, then decide you do notice a difference using your dedicated spur(s).

quote:

Originally posted by NaimThatTune:

* Earthing - my house has a rubbish earthing system and the metal gas pipes in the road outside were recently replaced with plastic ones - should I compound my internal disarray by proposing we dig up my patio and connect to a dirty great earth rod buried in the front garden?

You seem somewhat confused here. An earth rod is literally that. A long stiff pointed rod! It is hammered vertically into the ground. As such it requires very little ground area and hopefully no excavation. The problem is actually hammering it into anything but virgin loam or clay. A rock will stop it dead on the descent.

I hammered my own shiny commercial rod in near the house using a dirty great lump hammer and was lucky to be able to reach full depth. It was damned hard work! The cowboy electrician then connected the earth cable via a heavy clamp.

Previously I had soldered my system earth to a length of 1/2" copper pipe buried in the lawn. Depth is important though to ensure moisture allows good conductivity between soil and rod.

There have been reports in other threads on watering the ground around your earth rod to improve system performance audibly. If your water table is as high as my own then you can avoid this interesting exercise.

Do a forum search for "earthing". We had some valuable contributions here a while ago.

Edit: I see you are in Bath. Good clay subsoil should be helpful in hammering your rod if you aren't in the town centre where you are more likely to hit roman remains.

quote:

Originally posted by Nime:
The cowboy electrician then connected the earth cable via a heavy clamp.

Previously I had soldered my system earth to a length of 1/2" copper pipe buried in the lawn. Depth is important though to ensure moisture allows good conductivity between soil and rod.

My own earth rod (three connected lengths, total of 12 foot depth) is connected via a clamp, which has corroded. When I queried on PFM about soldering instead, I was told that the weather would attack the solder, and be worse than a properly installed clamp, which needs to be waterproofed with some sort of self-sealing electrical tape, apparently.

Since my system sounds worse with the corroded clamp in place (and I can't get the damn thing off!), I now run my system with it disconnected (ie just the mains earth in place).

cheers, Martin


PS I'm also told you need to be very careful how you connect an earth rod, unless you are disconnecting the mains earth. Expert help required. If you are planning to disconnect the mains earth, you surely need installation by a specialist, and probably have it checked regularly after that (and warn the buyer when you sell the house). A poorly functioning earth connection will kill you if you get a live-to-earth electrical fault. It will make the hifi sound worse, too.

I know of one poor sod (Ken C, I think), who has his Supercap connected to mains earth, and an earth rod connected to the binding post on the back of his 52. One live-to-earth fault anywhere in his property [possibly any property on his street], and he'll be feeding 240V through the circuitry of his 52. Try explaing that to your insurance company!!!

Ah! Ye olde independant earths! I remember something about this in our last forum chat about earthing. There was even talk of attracting lightning indoors via this route!

I keep wondering whether I shouldn't earth my 1.25 meter mini Jodrell Bank out on the lawn. It's boring having to unscrew the plugs every time we go out just in case of lightning.

Hi All,

Nime - I think perhaps I have confused you - I'm aware that an earth rod is a big spike, however, at the front of my house there is a small patio between house and garden - I'd have to remove at least one row of slabs and dig a channel below in order to wire the earth rod up to the earth wiring in the house. I would do this only if it was worth it. Thanks for the extra explanation, though! I'll take your advice and search on 'earthing' - though I know the basics I'm sure there is much to learn. And yes, my clay-like soil is soft and tends to hold water well, which frankly are its only redeeming features. The need for a garage drove me out of Bath city centre several years ago, sadly.

The phase of houses I live in were built in '62, and apparently earthing was much neglected at the time of construction - a number of my neigbours who have owned their houses since new have mentioned 'having had an earth put in'. This scares me just a little bit...

garyi - thanks for the URL - I'll look into it. Never thought of LED technology in the kitchen, too - do they really give out enough light for avoiding accidents with sharp knives? (I note you have 14, though).

Chumpy - I did some experiments a while back measuring voltage drops on spurs whilst placing load elsewhere on the system (boiling the kettle). Indeed the spur voltage dropped just as much as any other outlet in the house. I have a feeling that one competently installed high quality CU may be enough. Though I plan to confer with the electrician on this, I fear he may be a little more 'expenditure biased'.

Martin - Thanks for the words on clamping - I'll see to it that any connection is made in a belt and braces fashion and protected from weather. Any reason why a few thick coats of an underseal-like compound wouldn't do just the trick? In your situation, is there any reason you can't cut the wiring up close to the rod and reconnect properly just below the stricken clamp?

Speaking of being careful, I heard the IEE domestic earthing document/bible is 88 pages of A4 in length. Either they take a while to get to the point or there's more to this than one might initially assume!!

Thanks!

Richard.

quote:

Originally posted by NaimThatTune:
In your situation, is there any reason you can't cut the wiring up close to the rod and reconnect properly just below the stricken clamp?

Richard,

it's because the new clamp would have to be slid past the old one.

cheers, Martin

PS Sorry, Kuma.

I'm having my new house re-wired and simply told the electrician that I required 2 x 10mm2 dedicated spurs from separate circuit breakers terminated in 2 x 13amp unswitched double sockets. This was the recommendation that came directly from Naim.

Easy enough to do when you're re-wiring....

Although my electrician slightly raised his eyebrows, he said it was no problem.

Earthing will be normal, through the mains..........

How far does one go?????????????

quote:

Originally posted by Martin Payne:

it's because the new clamp would have to be slid past the old one.

The clamp on my earth rod is like a little inverted cup. This keeps rain out of the contact surfaces. One presumes a rod could be sawn off just below the original clamp and a new clamp placed on the remaining stump of rod?

Martin - ah, I see, though maybe Nime's suggestion or a (patient) hour with a Dremel or similar might release the stuck clamp. Up to you...

Blythe - nice to hear from someone in the same boat - sounds like your normal earth is/will be good enough - mine is not. Would the connection from an earth rod would be commoned with the house earth. Is this bad? Could I end up in a situation where my earth rod could effectively be the only decent earth connection for a number of my neighbour's houses, not just my own? Anyone? Bueller?
Is there anything special about your circuit breakers used for the hi-fi spurs?

I may go with:
a) a seperate ring style circuit (i.e. two sets of T+E cable but joined up between multiple sockets)

b) seperate spurs - one for each socket - would need about 6
or
c) seperate spurs going directly to IEC plugs which means hefty cable coming out of the floor with a mind of its own.

If I wanted to sell the house later without more wiring work, c would be out, so I guess (a) or (b) would be the preferred options, using normal rectangular 13A sockets rather than 15A round pin ones.

Nime - the cap sounds a good design - but I was expecting any earth rod to be completely buried with no part protruding above the soil - is this not how its done?

I'll check up on the earthing threads...

Cheers/Thanks,

Rich.

For goodness sake talk to an electrician!!!!!!

* what are your thoughts on whether an electrician is likely to be happy to install heavy grade (10mm2) cable to the hi-fi area/sockets.

Any electrician should be happy to do this it will just cost you more.

I would not recommend connectinf straight to the hifi from the CU. You cant get a 13A MCB.

For Starters:

As all house wiring has come under new regulations, you will find that a respectable electrician will not 'stray' from what is right as prison might await him.

of course, you will be able to tell him exactley what you want and where. You should find that a seperate ring circuit OR radial will be sufficient. I have a radial from my fuse box on a seperate MCB and it improved everything without doubt.

As for plugs, how far do you really want to go?
13A plug tops are more than adequate for any system. Personally i feel anything more would be a waste of time/money.

Earthing: if you know you already have an earth rod in the ground for your house then yes, a seperate one for the system curcuit would be a benefit. Most houses with overhead or underground supply cables have whats know as a 'Protective Multiple Earth' (PME). This is basically a 100A 'live' cable with a steel wire around it to protect it. The armour also serves as the neutral return AND the earth conductor for the house supply. An easy way to check is to look at your meter. If it has a smallish (10mm dia) black hard cable supplying the meter with a seperate brass earth block screwed to the board sumwhere then you have PME. If not you have the earth rod system.

Hope this is of some help but as i said, get hold of a decent electrican, tell him what you want and im sure ho will be happy to advise accordingly.

As for the lights in the stairs........its your house
Regards

Hi NiceGuy,

Yes - I have booked an NIC/EIC qualified electrician to visit my house for a consultation in about two weeks' time. He'll do all the work and certify later. But thanks for stressing that point. Safety and conformance to regs are my main priorities here (with a kicking sound system and a kitchen full of appliances that don't interfere with it a close second ).

So as to make the best of the meeting with the electrician, I wanted to poll a few opinions here first, because if I didn't know of a particular concept, I wouldn't be able to ask for it! [I'm not relying on the electrician to be a hi-fi buff and of course this is also about the whole house not just the hi-fi bit].

quote:

I would not recommend connectinf straight to the hifi from the CU. You cant get a 13A MCB.

This is valuable advice - thanks!

quote:

[Context: Looking at the meter] If it has a smallish (10mm dia) black hard cable supplying the meter with a seperate brass earth block screwed to the board sumwhere then you have PME. If not you have the earth rod system.

I don't have a seperate earth block as you describe, yet AFAIK the house has no earth spike - just clamps onto the gas and water pipes. The meter only has thick grey wire for L and N going to it from the supply into the house, and no onward connection of anything that could be an earth between meter and fusebox. The Fuse box has a pathetic straggly (unsheathed) wire going from an earth terminal to a gas pipe, and that's it. As an aside, the electrician who worked on the house next door refused to fit metal bodied light switches (the sort of retro look ones) because he said the house had NO earth. I know that unearthed systems have existed in the past but have been superseded by earthed systems. I really want to bring my house up to scratch with the proper regs.

I'm old enough to know myself reasonably well by now, and I guess what I'm really after is a good grounding (sorry!) in the concepts so that nothing much that the electrician tells me or recommends me will be a surprise or unfathomable.

From what I've heard so far:
a)a single new CU for the whole house should be OK, as long as hi-fi runs off a seperate MCB from the rest of it.
b)I could consider led lighting for areas that need to be 'usefully' lit (as opposed to 'moody' [read dim])
c)it sounds like the earthing needs major improvement, so don't be surprised if the subject of a dirty great pole being hammered into the garden comes up - time to dig up () my drainage survey plans from when I bought the house.
d)standard sockets should be OK, (from which I would use the stock Naim power leads). Mind you, regarding how far I may want to go - how much do quality sockets/legal sockets of a better type (perhaps unknown to me) cost compared to a reasonably high spec Naim system, even if they only give a tiny performance gain?
e)the prospect of a term in jail probably means the electrician won't be a cowboy
f)no one seems to particularly like my plan of lights up the stairs ...

To re-iterate an earlier point - has anyone used the braided Kimber type power cable - if it was cheaper, I'd probably just go for it anyway but last time I looked I remember thinking it was mucho-expensivo.

And, not forgetting the mess and fuss angle - I'm going to have to be lifting floorboards and all sorts of things I expect. Plus I'll have to virtually move out of the house for a few days and cover all my furniture in plastic to avoid the mess and dust?

Anyone know if you can hire short term storage for smaller items such as chairs and tables to help make the house a little more, er, navigable? [I'll try to find out myself, of course, but if anyone happens to tell me this I'd be grateful]

Cheers!

Rich.

Dear Rich,

The standards used as the minimum acceptable by electricians were apalling right into the early 70s. Non-earthed lighing circuits were the norm, and are definately not on. The cases of strip-lights can be lethal if wired in in those days. I guess this is where your electrician is coming from with unearthed circuits, but I don't think it was standard for sockets to be wired like that. I lived in a house that had a DC generating set in the 1920s, and the old wiring was still there (but not in use), and that had a very interesting approach. One core of copper ran down rubber insulation within a lead case, which presumably acted as the negative. I would have thought that the sysytem was bound eventually to be a death trap, or fire hazard! The sockets had brass surounds and some sort of bakerlite plate carried the two round pins. Interestingly the set was shared by two big houses and the shed that housed it did burn down through an electrical fault. Proper mains was installed in 1961, and in 1967 the transformer caught fire and was ruined, when a new corn-drier fan overloaded it! The days without any electric were quite funas I recall...

Fredrik

In days of old, lighting circuits did not need to be earthed at all, hence the reason why you cannot fit metal face plates to your existing lighting system.

Dont panic tho, i have come across a lot worse!!!

As for the kimber cable, again, i wouldnt worry too much. It seems like a huge expense to me.

On the subject of earthing arrangements your visit from the electrician will sort that out. Not being able to see it i cant help you with it.
As for the rest of the house, now is the time to sort out any buits and pieces you want sorting ie possible home theatre cables buried in the walls?

Lots to think about eh?
It will be loads of hassle but worth it in the end.

Best of luck

Rich
using Pirelli T&E was recommended by my dealer for my spurs it costs about the same as normal T&E also 6mm not 10mm was recommended by him.

Hi Fredrik, Hi NiceGuy,

Yes, the standards are much better these days and I'm all for it being that way! I didn't know things were ever quite as bad as Fredrik explains, but I can tell you, even though better ways of doing things had emerged by 62, I think only a handful of them were employed at my house!! I can remember the frequent power cuts in the early seventies, when I was but a boy, and I thought they were great fun!

Btw, it's not me that wanted the metal faced light switches, 'twas my next door neighbour. Her relating the story of her house 'having no earth' is what prompted me to look at the installation in my house and decide to get it rewired.

I can't really see the Kimber plaited cable being that effective either - I'll stick with the fattest normal stuff that the electrician is happy to fit.

I certainly do have lots to think about - I think burying wiring (or maybe just conduit) for home theatre wiring is a darn good idea (along with lights up the stairs, of course ) I'll add it to my list.

The sparky is coming on 16th Sept, because he's busy until then (which I hope is a good sign). When he comes to conduct (!) his survey, I'll have to be positive (!!) about what I want and what potential () future improvements I have in mind.


Cheers!

Rich.

Edit: Hi Custard - thanks - 6mm is probably adequate but as I'm getting into so much upheaval and mess I may as well use 10mm even though it'll be awkward to install. Didn't know Pirelli made wiring!

quote:

Originally posted by NaimThatTune:
When he comes to conduct (!) his survey, I'll have to be positive (!!) about what I want and what potential () future improvements I have in mind.

Groan