Dedicated Mains (again)

[Mike Reed]

So, Mike, you are saying that the sparate radials you have has removed all conducted interference on your system? This sounds like I could do with something along these lines to solve my "neighbour" problem (see "Shaken Faith" thread); Are the radials all the same length? on a diferent CU, etc? Was immunity from interference the prime reason for fitting the dedicated mains? Or is there a big SQ improvement to be had as well?
Cheers,
Mort

No, MORT; I said that interference was much dimished; possibly eradicated, but maybe I didn't have much interference before, apart from my antiquated boiler; that rarely bothers me now and may well be air-borne.

My friend with a very similar multi-cable installation gets no interference. Both of us have a number of same length 10mm2 T & E cables running to a dedicated Memera with individual 32 amp. RCBOs. My house is detatched; his is a semi. 150 miles away.

No, this was not my main reason; it is my 5th or 6th installation over 3 different houses and 25 years, so I don't need a reason; it's a cost-effective no-brainer for dynamics, and, ergo, s.q. It really CAN'T be worse for interference, can it? (I'm being rather conservative here!).

There are a number of variations on the theme, many in PFMers' domiciles. We prefer one cable per piece of kit (+ spare?), which effectively future-proofs things and gives individual convenience/control/safety.

The only major cost of having multiple cables over a shared individual is the RCBO (around £50 each) as the larger c.u. (Memera) is little more than its smaller unit, and cable is not prohibitive when bought as a reel. Tails, connection box and 100amp main fuse (if needed) are required regardless.

Hope this helps.

 

[oceanobsession]

No, MORT; I said that interference was much dimished; possibly eradicated, but maybe I didn't have much interference before, apart from my antiquated boiler; that rarely bothers me now and may well be air-borne.

My friend with a very similar multi-cable installation gets no interference. Both of us have a number of same length 10mm2 T & E cables running to a dedicated Memera with individual 32 amp. RCBOs. My house is detatched; his is a semi. 150 miles away.

No, this was not my main reason; it is my 5th or 6th installation over 3 different houses and 25 years, so I don't need a reason; it's a cost-effective no-brainer for dynamics, and, ergo, s.q. It really CAN'T be worse for interference, can it? (I'm being rather conservative here!).

There are a number of variations on the theme, many in PFMers' domiciles. We prefer one cable per piece of kit (+ spare?), which effectively future-proofs things and gives individual convenience/control/safety.

The only major cost of having multiple cables over a shared individual is the RCBO (around £50 each) as the larger c.u. (Memera) is little more than its smaller unit, and cable is not prohibitive when bought as a reel. Tails, connection box and 100amp main fuse (if needed) are required regardless.

Hope this helps.

Can you help with the 100amp fuse im told that you need to replace the holder to fit a 100amp fuse mine is made by bill switchgear it has 60amp on the fuse holder. also when you fit the mr30 field fit rcbo do they fit to the mcb (mini circuit breaker) its more expensive this way but im told its better
they are rated at 63amps would this be right .

 

[Mike Reed]

Can you help with the 100amp fuse im told that you need to replace the holder to fit a 100amp fuse mine is made by bill switchgear it has 60amp on the fuse holder. also when you fit the mr30 field fit rcbo do they fit to the mcb (mini circuit breaker) its more expensive this way but im told its better
they are rated at 63amps would this be right .

Gosh ! I'm no electrician (who is definitely needed on a legal basis alone in any ded. mains install), so cannot answer your questions.

I do vaguely remeber, however, that a 60 - 80 amp fuse holder needs upgrading but I may be wrong there; could depend upon age and type.

Don't understanf your mention of fitting an RCBO to an MCB. An RCBO IS an MCB plus an RCD. 32 amp. RCBOs are fairly standard, but there's one PFM member who has doubled that up. Theoretically I s'pose it's better; but safer? No idea, sorry .

 

[martin clark]

The main incoming fuse is property of your Supplier. Do Not tamper.

If it matters to you enough then call 'em up and tell them you want to install an electric shower and organise an upgrade of the incoming fuse to suit.



[size=-1]NB that 60A incoming fuse in no way seriously or even marginally affects what your hifi sounds like - takes >>200A sustained to break it reliably[/size]

 

[thegreathopper]

As someone who has been an electrician for over 30 years and wired thousands of MK sockets you have to be some sort of Clown shoe to wire a radial with 10mm twin and earth.

What not go the whole hog and wire your sockets with a 315 mm 3 core steel wire armoured cable and fuse it with a 500 amp HRC fuse. I guarantee it will sound the same as a standard 32 amp ring main wired with 2.5mm twin and earth.

 

[taz]

when I did mine i used 6mm t&e wrapped in mylar film down the whole length to act as a shield, i used a brand new earth block connected at 2 points, 1 being the original which I also changed for a new one, every contact point was cleaned and polished and I used a plaited earth wire with 3 2.5mm plaited together and silver soldered at both ends, it eas a pain and tight but it's a cracking earth that was barley readable in resistance. I used silver plated mains sockets at the other end, the run was 15m approx. I also spent hours cleaning the mini consumer unit which runs of the main consumer unit so is in fact double protected if you like, I allways tend to use the biggest and best when it comes to electrical stuff and over do it really but I spent most of my life working on minimum of 132KV up to 400KV so this 240v stuff seems a bit light weight, I run my hifi from a home made filter I made up with decent home made mains cables, I am a believer in cables making a difference to a point. As for regulations etc then by all means follow the rules and get a spark in to do the job, but when my ole man was allive he was given a new office at work, his secratary wasn't doing anything on day 2 so my dad asked why ? she said there is no plug on the electric type writer, OK said dad and toddles down to stores to grab a plug where he is told NO, eh he say's so the stores bloke says your not qualified to put a plug on, it's a job that's booked for thursday when one of the sparks is free. so no plug for guess who,???? chief Electrical Engineer C.E.G.B. in charge of the North west of England, with letters after his name and commendations to go with it ?
most of the law is crap, it's just there to stop the real thickies buggering things up which happens, I know one.
I don't know anything past 13th edition so I don't know whether you can do most of the work and get a reg sparky to connect up and sign it off, that's what I did saving me 2 hours labour at £45 an hour. maybe someone on here can verify that

 

[Mort]

Taz,
Can you tell me what the filter comprises of? Or is it a secret design
Most people are of the opinion that a filter takes the life out of the music, reduces dynamics, etc. but I assume that isn't your experience? I would be very interested to know more about this filter.
Also, what is the idea behind a plaited earth cable? What effect does it have on the sound? Finally, it sounds like you have 2x RCBO's or MCB's in the circuit - some people say that they affect the sound and you should have as little as possible in the circuit. Do you follow this theory?
Cheers,
Mort

 

[IWC Doppel]

As someone who has been an electrician for over 30 years and wired thousands of MK sockets you have to be some sort of Clown shoe to wire a radial with 10mm twin and earth.

What not go the whole hog and wire your sockets with a 315 mm 3 core steel wire armoured cable and fuse it with a 500 amp HRC fuse. I guarantee it will sound the same as a standard 32 amp ring main wired with 2.5mm twin and earth.

So you have tried then ?

 

[Mike Reed]

As someone who has been an electrician for over 30 years and wired thousands of MK sockets you have to be some sort of Clown shoe to wire a radial with 10mm twin and earth.

What not go the whole hog and wire your sockets with a 315 mm 3 core steel wire armoured cable and fuse it with a 500 amp HRC fuse. I guarantee it will sound the same as a standard 32 amp ring main wired with 2.5mm twin and earth.

I don't doubt that you're an electrician, but I have grave doubts about your cognisance of quality audio installations.

Have never heard the label 'Clown shoe' before. 'Clown', yes, but why 'shoe', and why should clown be a proper noun?

An utterly preposterous statement all round, i.m.o.

 

[cooky1257]

What is the benefit of using 10mm T&E over 2.5mm?

My now deceased bro was a consultant electrical engineer for Alexander Gibbs , he was a BSc C.Eng MIEE he wasn't qualified to sign off a house rewire-different quals/training and accreditation.

What is the Mylar screening out?

Isn't trying to force 10mm into domestic sockets actually dangerous as it strains the screw and will work loose over time?

Where is the evidence that 'better than mains earthing' is beneficial, how, why, as we are dealing with 240v @50hz(sometimes) this purity should be easy to measure.

Does your hifi sound better after heavy rain?

Is arranging your star earthing actually in a shamanistic/pagan/radio telescope star shape a bit mental?

 

[Mark Grant]

Any electrician I can think of would run either 2.5mm or 4mm twin and earth because thats what he buys by the palletfull.

Just make sure that the electrician is using genuine and approved cable, there are lots of counterfeit electrical cables in the supply chain and installed in peoples houses and businesses. ( it's been going on for years)

Homebase and Focus DIY where caught selling counterfeit cable a while ago:
http://www.aci.org.uk/news_more.asp?news_id=21&current_id=1

http://www.aci.org.uk/page/93/Safety-Video.htm

http://www.voltimum.co.uk/news/1314...hting-fake-and-dangerous-electric-cables.html

http://www.aeicables.co.uk/ 20% of cables are fake/non approved etc, apparently..

-

 

[Mike Reed]

What is the benefit of using 10mm T&E over 2.5mm?

ANS. Presumably lower impedance


My now deceased bro was a consultant electrical engineer for Alexander Gibbs , he was a BSc C.Eng MIEE he wasn't qualified to sign off a house rewire-different quals/training and accreditation.

What is the Mylar screening out?

Isn't trying to force 10mm into domestic sockets actually dangerous as it strains the screw and will work loose over time?


ANS. No, as you shouldn't need to force them and they won't work loose.


Where is the evidence that 'better than mains earthing' is beneficial, how, why, as we are dealing with 240v @50hz(sometimes) this purity should be easy to measure.


ANS. Adding an earthing rod (or more) as an addition to your domestic earth can lower the impedance still further, BUT ONLY IF YOU HAVE AN EXISTING EARTHING SYSTEM WHICH IS COMPATIBLE.

Does your hifi sound better after heavy rain?

ANS. Hmmm ! Must listen to Handel's Water Music to ascertain. Wet ground is generally considered to be better for earthing than dry due to conductivity properties.

Is arranging your star earthing actually in a shamanistic/pagan/radio telescope star shape a bit mental?

ANS. No idea, sorry.

 

[cooky1257]

Hmm so lower impedance in the mains supply to your hifi is a good thing because?

Telling me it lowers the impedance of the domestic earth doesn't explain the benefit-that's why I asked if the hifi sounds better after heavy rain.

 

[taz]

which questions (if any) where aimed at me ?
not 10mm I didn't use that just 6mm, as for the earthing mine was heavily oxidised and obviousley hadn't been touched in over 20 years or so, that's why I replaced all the earthing, I also (nothing to do with hifi) re earthed many water pipes that where the same.
as for the plaited earth cables I made, do they sound different ? dunno never done a blind test, just picked the idea up from a d.i.y website, not sure if it was TNT. I figured it couldn't do any harm and the cleaning of all the earths certainly didn't do any harm. the Mylar wrap was to help reduce any rfi/emi in the cable, now to answer Mort
Hi Mort, I live in a house with my family, we live on top of a big hill that is prone to lightning strikes, my AV setup NEEDS protection, it's not a case of what I would like to do but needs must, the main consumer unit feeds the secondary consumer unit on the non protected side so doesn't come in contact with the circuits for the rest of the house, since fitting this radial circuit I have removed a lot of noise from the AV Circuit, then I make up my mains cables using quality cable and plugs, the filter was originaly a cheap Tacima or something filtered mains socket, I just removed the filter board swapped a few bits and fitted it all in an insulated box with a silver mains socket on top, I need about 6 sockets so I use a Monster multi way socket for all the AV stuff and the filter I made for the cd player and amp, again I have not done any back to back comparrisons but again when I connected the amp/cd to the filter it lowered the noise floor even further, I have used several filters in the past, some sounded better some not, it's a suck it and see job, there always seems to be trade off's with any mod and in my experiance more often than not things don't tend to sound better or worse just different. as i am always broke I tend to do a lot of DIY stuff, try this idea try that, i have just made a new balanced i/c using high quality coax and solid 0.5mm silver that sounds better than my original VDH D102 MK3 and I have many more ideas i would like to try, iv'e been messing with hifi for over 30 years now and i'm still learning all the time

 

[IWC Doppel]

Hmm so lower impedance in the mains supply to your hifi is a good thing because?

Telling me it lowers the impedance of the domestic earth doesn't explain the benefit-that's why I asked if the hifi sounds better after heavy rain.

In answer to your weather question, it is a yes, less so now I am using the incoming earth without running via lots of commections through the house. But running earth rods wet did improve things.

One thing I did read was how poor earth internally within a component causes issues as there will in real life be a meaning full potential diference between circuit points (especially different kit) Measurements of s/n ratio was drmaticaly effected when a circuit 'hummer' was attached to one supposed earth of a component.

I simply listen and decide

 

[Pete the Feet]

They say the simple act of disconnecting DIN plugs and re-connecting them again can clean up the pins and thus improve the connection and thus sound. Also similar can be said of the 3 pin mains plugs. I wonder if just carrying out this simple task just once in a while could have the same effect as a mains upgrade or even be the reason for some of the improvements.

 

[taz]

definatly Pete just cleaning all your connections every now and then can make a big difference, just try it if you don't think so

 

[Pete the Feet]

definatly Pete just cleaning all your connections every now and then can make a big difference, just try it if you don't think so

I don't dispute it, I just wondered if this was the improvement people hear when upgrading the mains after re-connecting everything.

 

[IWC Doppel]

I don't dispute it, I just wondered if this was the improvement people hear when upgrading the mains after re-connecting everything.

Nope, When a-b against the existing ring main (I wired additional connections) this shows the difference I have referred to, a very worthwhile one and fundamental in my view to how the system has sounded since

 

[Mike Reed]

They say the simple act of disconnecting DIN plugs and re-connecting them again can clean up the pins and thus improve the connection and thus sound. Also similar can be said of the 3 pin mains plugs. I wonder if just carrying out this simple task just once in a while could have the same effect as a mains upgrade or even be the reason for some of the improvements.

ANY plugs withdrawn and reinserted may benefit (minutely) by the inherent cleaning effect. Better contacts equal better dynamics equal better sound.

Similar to installing ded. mains? Totally different ball-game.

Don't like plugs and sockets, so doesn't affect me, but interconnects do benefit. However, I'm too lazy, and the Chord and Naim cables I have are just too much of a pain (too stiff or delicate) to fiddle around with.