IIUC the tests I've been looking into by Ben Duncan on Russ Andrews mains
cables were done with the earth lead unconnected. This makes me wonder.

Is it legal in the UK to *not* connect the 'earth' wire at the mains socket
end if it is used with a standard 3-pin socket?

Also, I tend to assume it is normal/good practice to earth one item in the
system, usually the amplifier when 3-wire UK mains is provided. Is this not
usual these days?

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

On Fri, 26 Jun 2009 13:18:52 +0100, Jim Lesurf
wrote:

IIUC the tests I've been looking into by Ben Duncan on Russ Andrews mains
cables were done with the earth lead unconnected. This makes me wonder.

Is it legal in the UK to *not* connect the 'earth' wire at the mains socket
end if it is used with a standard 3-pin socket?

Also, I tend to assume it is normal/good practice to earth one item in the
system, usually the amplifier when 3-wire UK mains is provided. Is this not
usual these days?

Slainte,

Jim

Well, my amplifier certainly ash an earth connection (and so does my
PC, hence the isolating line transformer for the sound card). But all
the auxiliary stuff has mains plugs with a plastic earth pin. They
have kite marks, so I presume they are legal.

d

In article ,
Jim Lesurf wrote:
IIUC the tests I've been looking into by Ben Duncan on Russ Andrews mains
cables were done with the earth lead unconnected. This makes me wonder.

Is it legal in the UK to *not* connect the 'earth' wire at the mains
socket end if it is used with a standard 3-pin socket?

If it's Class II (double insulated) as most equipment is these days, then
yes. Lots of things have only a two core mains cable.

Also, I tend to assume it is normal/good practice to earth one item in
the system, usually the amplifier when 3-wire UK mains is provided. Is
this not usual these days?

Mostly, since it might help prevent interference of some sort. But not
always necessary from a safety point of view.

Remember ages ago a friend bought a complete Pioneer sound system. Amp,
tuner, cassette, turntable and speakers.

All with three core mains leads. Apart from the speakers. Wire it all up
using the supplied phono leads and it hummed like a good 'un.

--
*Virtual reality is its own reward*

Dave Plowman London SW
To e-mail, change noise into sound.

In article 4a45bd62.1151755296@localhost,
Don Pearce wrote:
But all the auxiliary stuff has mains plugs with a plastic earth pin.
They have kite marks, so I presume they are legal.

You quite often see a 13 amp to 2 pin adaptor fitted - with a tamper proof
screw so it can't be removed. To save fitting a UK mains lead. But these
have a brass earth pin.

--
*Does fuzzy logic tickle? *

Dave Plowman London SW
To e-mail, change noise into sound.

In article , Dave Plowman (News)
wrote:
In article , Jim Lesurf
wrote:
IIUC the tests I've been looking into by Ben Duncan on Russ Andrews
mains cables were done with the earth lead unconnected. This makes me
wonder.

Is it legal in the UK to *not* connect the 'earth' wire at the mains
socket end if it is used with a standard 3-pin socket?

If it's Class II (double insulated) as most equipment is these days,
then yes. Lots of things have only a two core mains cable.

I was asking because the cable being tested does have an earth wire, and I
think is sold with connectors fitted. I had thought that we were expected
to use an earth if the connectors and cable include it, but was unsure.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

On Fri, 26 Jun 2009 12:23:17 GMT, (Don Pearce) wrote:

Well, my amplifier certainly ash an earth connection (and so does my
PC, hence the isolating line transformer for the sound card). But all
the auxiliary stuff has mains plugs with a plastic earth pin. They
have kite marks, so I presume they are legal.

Could you possibly provide details of the isolating line transformer,
please? (My work laptop is eathed and causes some 'interesting' noises
when mains powered.)

Thanks,


--
Chris Isbell
Southampton, UK

On Fri, 26 Jun 2009 16:41:19 +0100, Chris Isbell
wrote:

On Fri, 26 Jun 2009 12:23:17 GMT, (Don Pearce) wrote:

Well, my amplifier certainly ash an earth connection (and so does my
PC, hence the isolating line transformer for the sound card). But all
the auxiliary stuff has mains plugs with a plastic earth pin. They
have kite marks, so I presume they are legal.

Could you possibly provide details of the isolating line transformer,
please? (My work laptop is eathed and causes some 'interesting' noises
when mains powered.)

Thanks,

Yup - I bought it in Maplin. It is a Shark, model VW43W ground loop
isolator.

d

In article 4a4aec56.1163774312@localhost, Don Pearce
wrote:
On Fri, 26 Jun 2009 16:41:19 +0100, Chris Isbell
wrote:

On Fri, 26 Jun 2009 12:23:17 GMT, (Don Pearce) wrote:

Well, my amplifier certainly ash an earth connection (and so does my
PC, hence the isolating line transformer for the sound card). But all
the auxiliary stuff has mains plugs with a plastic earth pin. They
have kite marks, so I presume they are legal.

Could you possibly provide details of the isolating line transformer,
please? (My work laptop is eathed and causes some 'interesting' noises
when mains powered.)

Thanks,

Yup - I bought it in Maplin. It is a Shark, model VW43W ground loop
isolator.

This makes me wonder as I've not checked. I have assumed USB carries ground
between units, so could produce a loop if both are earthed. Is this
correct?

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

In article ,
Chris Isbell wrote:
On Fri, 26 Jun 2009 12:23:17 GMT, (Don Pearce) wrote:

Well, my amplifier certainly ash an earth connection (and so does my
PC, hence the isolating line transformer for the sound card). But all
the auxiliary stuff has mains plugs with a plastic earth pin. They
have kite marks, so I presume they are legal.

Could you possibly provide details of the isolating line transformer,
please? (My work laptop is eathed and causes some 'interesting' noises
when mains powered.)

I bought a tray of 'GPO' spec ones off Ebay - designed to isolate a modem
from the phone line. The spec isn't brilliant - but they actually sound ok
for most things. Certainly better than the 300 - 3000 Hz you'd expect for
phone use. If you'd like a couple, mail me.

--
*The fact that no one understands you doesn't mean you're an artist

Dave Plowman London SW
To e-mail, change noise into sound.

"Chris Isbell" wrote in message
...
On Fri, 26 Jun 2009 12:23:17 GMT, (Don Pearce) wrote:

Well, my amplifier certainly ash an earth connection (and so does my
PC, hence the isolating line transformer for the sound card). But all
the auxiliary stuff has mains plugs with a plastic earth pin. They
have kite marks, so I presume they are legal.

Could you possibly provide details of the isolating line transformer,
please? (My work laptop is eathed and causes some 'interesting' noises
when mains powered.)


I was going to post a suggestion that you simply lift the earth on a
suitable extension lead, but then considered that it would most likely lead
to an hubristic outburst from the bed-wetters here, like Pucci.....

So, perhaps I won't bother....

:-)