Unswitched wall sockets

[winston1]

I am having an additional mains spur installed in my house. It will only be feeding a single double wall socket and will be connected to a 32A RCD within a mains consumer unit.

I've been told that I can not use an unswitched wall socket as "each circuit must have a switch".

Is this correct? All items that will be connected to these sockets have internal fuses (as do the mains leads), so is it dangerous using an unswitched socket?

Thanks.

Back to the original question. You can use an unswitched wall socket.

However for a single double socket use a 20A RCD not 32A. A double socket is rated at a lot less than 2 x 13A. Also using a 20A RCD allows it to be wired in 2.5mm cable rather than 4mm.

 

[diyer56]

This website is amazing!!

http://www.russandrews.com/product....2531020514292MMFEGSGEHSBQMNSH&showBasket=true
20m=£1,310

http://www.russandrews.com/viewinde...&customer_id=PAA2531020514292MMFEGSGEHSBQMNSH

 

[ekmdgrf]

Nice that they recommend a ring final for the audio socket. If I were charging £65 a meter, I would too!

Also like the dedicated hifi CU. The next logical step would be to see if you can get an audio grade Henley, meter and cutout. Might also be worth looking to see if you can move house to somewhere served by an audio grade substation?

 

[GAClarke]

Apparently removal of the switch reduces the impedance (so I am told).

Regardless of whether that is true or not, there was a noticeable improvement in the sound quality.

What rubbish! And the improved sound quality was noticed because you wanted to notice it. If someone moved it to a switched socket and standard extension cable without you knowing, you wouldn't notice.

Think of all the upstream switches and other equipment that you have no control of.....

Anyway, just my opinion!

<sigh>

Well, I respect the fact that you are entitled to your opinion but have you actually tried this? Are you talking from experience or just what you "think" would be the case?

You are asking this on a "technical" forum.
Most of the guys here have a good Electrical Theory knowledge.
Do you?
You must realise that the Hi-Fi industry is full of con men and purveyors of "snake oil".

The TINY impedances present in the electrical supply network will not affect any well designed audio gear.
Trust me... They won't.

Frank

FDJ,

No, I don't have a good electrical theory knowledge, if I had I likely wouldn't be asking a simple question here

Yes, the hifi industry does have its share of con men and snake oil although such sharp practices aren't restricted to this industry. The only way to differentiate between good and bad is to try it and see. That's why reputable dealers offer a money back guarantee. You're also less likely to "convince" yourself it is better if you know you can get a refund rather than being stuck with a dud that you paid for.

As for electrical theory knowledge - does this qualify someone to build high quality hifi electronics and fully understand everything that is going on? I suspect there is an overlap in skillset but doubt that one equates directly to the other.

Anyway, I have an answer to my original question. So many thanks to those who gave me constructive responses. As for the rest, well, if you are electricians by trade I do hope you don't speak to your customers face to face in the same way otherwise I doubt you'll get much in the way of word of mouth positive feedback.

End of thread for me.

 

[FDJ]

I used to work on a site where the mains was 230v DC.
The DC powered oven made the best Yorkshire Puddings....

Frank


(This is true... and I am qualified to design and build Hi-Fi and other electronic gear.)

 

[ekmdgrf]

I used to work on a site where the mains was 230v DC.
The DC powered oven made the best Yorkshire Puddings....

I bet they were the best sounding Yorkshire Puddings you've ever eaten.

 

[FDJ]

I used to work on a site where the mains was 230v DC.
The DC powered oven made the best Yorkshire Puddings....

I bet they were the best sounding Yorkshire Puddings you've ever eaten.

They were the best in ALL respects...

 

[ericmark]

I am having an additional mains spur installed in my house. It will only be feeding a single double wall socket and will be connected to a 32A RCD within a mains consumer unit.

I've been told that I can not use an unswitched wall socket as "each circuit must have a switch".

Is this correct? All items that will be connected to these sockets have internal fuses (as do the mains leads), so is it dangerous using an unswitched socket?

Thanks.

Back to the original question. You can use an unswitched wall socket.

However for a single double socket use a 20A RCD not 32A. A double socket is rated at a lot less than 2 x 13A. Also using a 20A RCD allows it to be wired in 2.5mm cable rather than 4mm.

What! The RCD amp ratting is for how much current it can carry there is nothing wrong with used a 63A RCD on a circuit protected by a 20A MCB. However there would be a problem the other way around.

I can see what you intended to say. But it is permissible to have a unfused spur from a ring final protected by a B32 MCB supplying a single twin socket using 2.5mm² cable.

 

[jabuzzard]

Apparently removal of the switch reduces the impedance (so I am told).

Regardless of whether that is true or not, there was a noticeable improvement in the sound quality.

What rubbish! And the improved sound quality was noticed because you wanted to notice it. If someone moved it to a switched socket and standard extension cable without you knowing, you wouldn't notice.

Think of all the upstream switches and other equipment that you have no control of.....

It will reduce the impedance, though anyone claiming it is noticeable is delusional unless the switch is in very poor condition. That said a specific circuit for a HiFi could have a noticeable effect in reducing mains born interference. However it would require that you have really rubbish HiFi equipment in the first place

Then again high end HiFi is stuck in something of a design rut. For example if your high end HiFi has a linear PSU that it is junk Why mess about with a linear PSU and the potential for mains hum, when a quality switch mode PSU could run at 120kHz or even as high as 500kHz totally outside human hearing and make mains hum a thing of the past? Why because the nutters that buy high end HiFi are conditioned to think that a linear PSU is the way to go because in the past SMPS did indeed operate in the hearing range. However things have changed and that went away over a decade ago.

 

[maltaron]

It always amuses me what hi-fi buffs claim, but unless they are playing top quality vinyl discs on a transcription turntable they will never notice any difference. Since the start of digital audio the term hi-fi is redundant. And most modern so called hi-fi buffs spend a fortune on so called brilliant equipment and the stuff an MP3 player up it.

 

[stillp]

Linear PSU or SMPS, any so-called "hi'fi" that is affected by a fraction of an ohm extra impedance in the 230V supply is clearly rubbish.