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The Story of the Surprising IEC Power Cord
Old 14th October 2019
  #1
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The Story of the Surprising IEC Power Cord

Today I took an IEC power cord apart, hoping to use the internal wires for a short bit of internal power wiring. It's power wire, right?

Well guess what: The wires inside were no bigger than 22 gauge and actually they looked more like 24 gauge.

Who woulda thought?
Old 14th October 2019
  #2
Lives for gear
10' of 22 ga wire is roughly 1/6 ohm (it's a little less... but for ease, I'm assuming a 5' cord so ten feet total of series resistance).

A piece of lightweight rack electronics drawing maybe 1 amp will therefore see 1/6 volt loss. Hardly enough to worry about, either in terms of voltage to the device, or heat coming off the wire. So if this cord is OEM with some small gear, sure. Cheap, sure... and I don't know if it's even code. But workable nonetheless.

OTOH, I wouldn't use that cord for my electric cooking grill.
Old 14th October 2019
  #3
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Not all IEC power cords are the same. The jacket of the cable itself typically would be stamped or labeled with the wire gauge contained inside. The one I happened to have at hand to look at is 18 AWG ("P.E. CO. 18/3 SVT"). I don't know for sure, but I thought in general UL listing required a minimum of 18 gauge for AC power cords...but I could be mistaken, or perhaps your cord wasn't actually listed.

It's often the same for "heavy-duty" style outdoor extension cords, which if one isn't careful in checking often turn out to be 16 gauge wire in a heavy outer casing. That's fine for preventing damage in relatively rough usage, but not so good for powering a large tool.
Old 15th October 2019
  #4
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I'm going to stop posting fascinating things here.
Everyone thinks that they have to explain it.
Old 15th October 2019
  #5
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analogguru's Avatar
 

Quote:
Originally Posted by lame pseudonym View Post
...... fascinating things ......
You should buy christmas lights. Some have thin aluminium wires surrounded by only one very thin copper wire...... fascinating.
Old 15th October 2019
  #6
Quote:
Originally Posted by lame pseudonym View Post
I'm going to stop posting fascinating things here.
Everyone thinks that they have to explain it.
Why stop? For me the explanations were more interesting than the fascination. It turned out well, me thinks.
Old 15th October 2019
  #7
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lame, you're not the only one who reads this forum.

You posted something of interest - for which I (among others) thank you. We replied, even though you probably already know Ohm's Law, because there are newbies who who want to learn how this all works. And because some day, someone might search for "power cord AWG" or something, and we don't want them to walk away thinking lightweight wire is good for most uses.
Old 15th October 2019
  #8
Most IEC cables are poorly made with thin conductors and zero shielding. Low cost 14 AWG and 9 AWG shielded litz power cables can be bought from Audio Advisor under the Pangea brand.
Old 15th October 2019
  #9
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One day I measured several IEC power cords in my spares box with a very nice 4 terminal Ohm meter. Some measured much higher end-to-end resistance than I expected.
Old 15th October 2019
  #10
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As a favor for a community college audio instructor I triaged a stack of cheap donated gear. At the same time I beeped out their mic cables. Just for fun I did their extension cords and loose IEC's as well. In one IEC, ground had no continuity. I cut one end off, and found the reason. There was a skinny little hot and a skinny little cold... and no ground wire.
Old 15th October 2019
  #11

Get the ones with the extra notch that are rated for higher temperatures....

I bet they don't skimp on conductor strands as much.


-tINY

Old 15th October 2019
  #12
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Brent Hahn's Avatar
 

Quote:
Originally Posted by tINY View Post
Get the ones with the extra notch that are rated for higher temperatures....

I bet they don't skimp on conductor strands as much.
I'm sure you're right. Fact is, though, I don't recall ever in my life "getting" one except with a piece of gear or something else electrical. I have a box somewhere full of them and I'm sure I've tossed way more than that.
Old 15th October 2019
  #13
Quote:
Originally Posted by Brent Hahn View Post
I'm sure you're right. Fact is, though, I don't recall ever in my life "getting" one except with a piece of gear or something else electrical. I have a box somewhere full of them and I'm sure I've tossed way more than that.


We had to buy some for the lab (a scope had a C16 inlet). I thought they may be for higher current... Nope, just higher temp.



-tINY

Old 16th October 2019
  #14
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you might not want to see how skinny the wires are inside the power transformer...

JR
Old 16th October 2019
  #15
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Quote:
Originally Posted by JohnRoberts View Post
you might not want to see how skinny the wires are inside the power transformer...

JR

Or the ones going to the speaker of your solid-state combo amp.
Old 17th October 2019
  #16
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The skinniest wires of all seem to be in my daughters headphones. Fyi.r.
Old 18th October 2019
  #17
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Quote:
Originally Posted by Farmboy presents View Post
The skinniest wires of all seem to be in my daughters headphones. Fyi.r.
I used to keep cheap Sony headphones around the studio with mini-to-TRS adapters, but people kept walking off with them. So I got some more and decided to solder the TRS's directly to the cables. Not fun in the slightest.
Old 18th October 2019
  #18
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Coincidentally speaker wires are usually the heaviest because A) consumers see them, and B) they handle more current than line cords.

Don't confuse insulation thickness with conductor gauge.

There is apparently an entire industry selling magic (improved) line cords. If a line cord makes an audible difference either the old one was bad, or the product has a horrible PS design.

JR
Old 18th October 2019
  #19
Gear Addict
 

My fascination with IEC cords is nearly always to do with how much people will pay for them in high end hifi circles... just found one that, at a meter in length, costs $20,900.
Old 18th October 2019
  #20
Quote:
Originally Posted by SoundSlinger View Post
My fascination with IEC cords is nearly always to do with how much people will pay for them in high end hifi circles... just found one that, at a meter in length, costs $20,900.

I bet it's pretty....



-tINY

Old 18th October 2019
  #21
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Quote:
Originally Posted by SoundSlinger View Post
My fascination with IEC cords is nearly always to do with how much people will pay for them in high end hifi circles... just found one that, at a meter in length, costs $20,900.
Sounds like the market is ready for me to unload my stash of original analog IEC cords. Not only do they sound warm but some even feel warm. Ymmv.
Old 18th October 2019
  #22
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Quote:
Originally Posted by tINY View Post

I bet it's pretty....
They are... Even the ones that are, er, only $1300 are pretty.
Old 19th October 2019
  #23
Pangea's look great and they start at about fifty bucks. 9 awg will help a power amp or large power supply. 14 awg covers the light stuff.
Old 19th October 2019
  #24
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Quote:
Originally Posted by Jim Williams View Post
Pangea's look great and they start at about fifty bucks. 9 awg will help a power amp or large power supply. 14 awg covers the light stuff.
If a 15A/20A mains branches only uses 14/12 AWG conductors between the outlet and the panel, a 9 AWG line cord should be more than adequate for a couple feet.

Of course more is always better and the customer is always right.

JR

PS: $50 is more sensible than spending thousands, but do not expect much (any?) audible difference.
Old 19th October 2019
  #25
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Quote:
Originally Posted by JohnRoberts View Post
$50 is more sensible than spending thousands, but do not expect much (any?) audible difference.
No, John... they SHOULD expect a major improvement, and then confirmation bias will influence their senses to tell them they hear a marked improvement.
They will be happy with their purchase, they do no harm to their setup, and no animals were harmed in making the switch. Beyond win-win, isn’t it?

Last edited by Bushman; 21st October 2019 at 01:20 AM..
Old 20th October 2019
  #26
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Quote:
Originally Posted by JohnRoberts View Post
If a 15A/20A mains branches only uses 14/12 AWG conductors between the outlet and the panel, a 9 AWG line cord should be more than adequate for a couple feet...................................
Some people don't understand Ohms Law and how it applies to series circuits.
Old 20th October 2019
  #27
Besides more than enough current, it's the shielding that's the benefit. If you run audio or speaker cables near or next to the AC mains cables that will help.
Old 20th October 2019
  #28
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such a lame pseudonym
Old 21st October 2019
  #29
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Quote:
Originally Posted by audiospecific View Post
such a lame pseudonym
“Badfoot” would be a lame pseudonym, in one sense.
Topic:
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