ac cord

[reddish75]

hi i want to make a nice looking ac cord and have found this wire
http://cgi.ebay.co.uk/ws/eBayISAPI.d...8772&rd=1&rd=1
will it be any good? plus any opinions on how to build would be a big help

thanks

[AndrewT]

Hi,
I am guessing when you say ac cord you means 240Vac mains cord.

There is no mention in the ebay ad of voltage rating of the insulation. It may well be adequate.

I think UK mains cables are rated to 600V or so.
Mains cables must be double insulated. Whether the teflon over kapton counts as double insulation, I cannot advise.

If you make up a three core mains cable I would seriously consider how you can arrange an overall robust insulation layer that can withstand repeated abuse.

Arrange adequate fusing before this cable and in addition consider RCCB protection.

[reddish75]

yeah i do mean 240vac, i have mailled him about ac use but have yet to hear back, however could i not put heatshrink over the wire to make sure it is sutibly insulated?

[Sonusthree]

Hi,
All the heatshrink that I have ever used has been way too stiff for power cord.
Try some around regular mains cable as a test to see what you think. You may have better luck.

[reddish75]

i have just heard back and the wire is rated to 600vac which in my eyes is perfect?
is the best way to build this cable to plait it or is there a better way?

[AndrewT]

Hi,
twist into a triplet just like a comventional mains cable and you get minimum spacing. This results in maximum capacitance and minimum inductance.
Plaiting forces a much wider spacing of the cores and results in less capacitance and more inductance.

If you believe that the main advantage of the exotic cables comes from the filtering effect of inductance in the cable before the line to line caps in the equipment then plaiting will attenuate the inteference more than the twisted triplet.

[mightydub]

I realize that I'm inviting a flame war here, but -

if changing the AC cord does anything to change the sound of whatever component it is serving as the conduit of power for, then that component has a poorly designed power supply.

Why should a few feet of AC cable, or "hospital grade" AC outlets, or any other such stuff inside the house magically correct for all of the RF and other noise that is coupled into the miles of power lines between the generation plant and your house? Or the noise coupled into your power line from the ancient motor in your neighbor's refrigerator or vacuum cleaner?

Think about it - if the parasitic R-L-C of a few feet of AC cable built of some exotic wire and construction makes a difference, then the power supply is not doing an adequate job of converting AC to DC, providing bulk capacitance for peak current loads, and/or filtering out RF or other power line noise.

[Pit Hinder]

*Only* a flame war? You'll be tarred and feathered, old man - by the people who flog three-digit-$ mains cables to the "it's expensive, I need it" crowd.

Pit

[analog_sa]

Originally posted by mightydub
I realize that I'm inviting a flame war here, but -

if changing the AC cord does anything to change the sound of whatever component it is serving as the conduit of power for, then that component has a poorly designed power supply.

You are certainly right. Unfortunately these are the only ps designs we know. If anyone can suggest a PS design that completely rejects the PC effects it will be the greatest achievement of audio this century.

Curiously, regeneration, as known does not eliminate PC effects. No idea if 'never connected' does but i'm not holding my breath.

[reddish75]

its not that i need it to improve sound, i just need a longer cable and was wondering if there was a right or wrong way of building a power cord