Please assure me I'm not going to burn my house down.


I recently bought some new mono class D amps to replace a stereo class D. I had a pair of identical diy power cords connected to the stereo amp and my preamp.

Well, with monos I was obviously going to use the identical power cords. So I needed a new PC for my pre, as the older diy version I had laying around just used thhn wire from Lowe’s and didn’t sound great. So, after some thought and research, I decided to make a PC out of cat 5 plenum cable. I kept it in its blue sleeve (containing 4 twisted pairs) and then I braided 3 lengths together for each conductor. I then took those three braids and braided them. What I have sounds incredible and I’m fairly confident that it is safe electrically.

Please reassure me. Or tell me I forgot about x, and that I should cease and desist. Or laugh at how cheap I am...

But really, I’m not going to start a fire here, am I? 8 conductors per length x 3 lengths for each conductor equals 24 strands of 24awg. Which equals 10awg for each conductor...
128x128toddverrone
This ISNT advice on safety. Just perspective using a seemingly questionable PC.

I used one of these for several years without any problems. The construction possibly Iis even more dagerous appearing!

http://shop.mapleshadestore.com/Double-Helix-MK1-Power-Cord/productinfo/MK1PC%2DST/

it made amp, source even TV perform noticeably better. The clear film eventually became torn in several areas, Scotch tape just made me feel uneasy about its safety.

Speaking with the company, I was told Pierre REMOVES the film in his setup!.



You may equate the gauge, but man, you are playing with fire, literally.

Let's say something does go wrong.... you could be held legally liable even if you do all the math right! :)

Much better to get a Connex shielded power cord and make your own.

Also, part of what you are not including in your calculations is the insulation temp rating. The insulation around Cat 5 signal wiring assumes nearly no current at all, while power cord insulation is rated to withstand the heat of the conductor at full current.

Best,


E
I actually thought about the insulation temp.. I purposely used plenum rated cable, which has Teflon insulation instead of PVC...

Do you think an insurance company would look more kindly upon diy cables of a different variety? I'd imagine they'd poo poo any diy cable.. But I'm not sure.
toddverrone-

yeah, it came with a modded CD deck. I was hesitant to use it. Apparently they have sold many over the years without disaster. Thought it lived up to its claims, but I moved on. I use the ribbon interconnects, which also are flimsy and delicate.

 Definetly wouldn't have kids or pets near it. 
Bad idea. Even if you don't want to go big time with power cables, get a little scratch together for something decent, something that won't invalidate your home insurance if a fire breaks out, like these:
https://www.audiogon.com/listings/ac-cables-component-of-the-year-award-silnote-audio-gl-reference-p...
@mani-2 my other power cables are a helix design I got from williewonka (agon name), which I then made from the conductors from the yarbo 9000 series PCs with silver coated copper neutral helix and a thhn wire ground helix, both wrapped around the yarbo conductor. I used sonar quest plugs. So I know how to make a great sounding cable from proper components..
 I was curious what a braided architecture made from individually insulated, small diameter solid conductors would sound like. That's why I tried cat 5.

I could do it with proper small diameter power cable..
Check your home owners policy because if you made one mistake your house could be toast hope not though.
www.signalcable.com as low as $49. I have zero affiliation with them, other than buying a couple. Save yourself the headaches for a few bucks.
Please use a standard IEC power cord until you can buy or make a proper power cable. While the copper in the CAT 5 may be up to the task, the insulation most certainly is not. Way too thin for the amount of current flowing through a 120v 60Hz power cord. 

Nothing wrong with a home made cable, as long as the cable you choose is made for the voltage and current you are using.  That's why regular power cords have that thick rubber coating on each wire, with a thick rubber coating over all conductors. It is rated for household current. CAT 5 is not. CAT 5 can be brittle and break from too much bending, it's rather fragile compared to a stranded copper wire used in an IEC power cable. A custom cable may sound better, but a standard UL approved wire won't destroy your sound either. It'll be fine until you get a proper cable. 
I'd keep the local fire departments number on speed dial for sure!  Maybe go down there and get a few firefighters cell phone numbers also!  Go to the local hardware store and get a few fire extinguishers on hand and a large bottle of water laying around.  Make sure you have access to the main fuse box to cut the power to your home electric when the smoke and flames start billowing up to the ceiling.  Other than that, I think you are fine.

Happy Fire extinguishing Blaze!
 
I would be most concerned about termination. It is easy to braid wire together - and it's easy for wire to become unbraided at the termination. If the wire does unravel, then you may find one or two conductors carrying all the current. Then things unravel.

Second problem is teflon. If things unravel, those few conductors are going to get hot. If teflon gets hotter than about 500 F, things go badly wrong - it decomposes into highly toxic gases, including HF. You don't want to risk HF. Really, you don't.
@terry9 the cable is well terminated. I stripped the individual wires and crimped spades at the end of each bundle. I then put heat shrink up over any bit of exposed metal, other than the spade. These babies are solidly terminated.

As for the Teflon melting, that will obviously not be a problem with all the conductors functioning, which they will be. 

Great points, though.

So far, I've not really heard any valid reasons backed by theory, other than @erik_squires suggestion that the insulation may not be up to the task..
Do you live alone?  And alone in a single-family house, not an apartment/condo/duplex where others live in the same building?  If you'd answer "no" to any of that then please just get a commercially acceptable power cord.  And please get it now - you just cannot do that to others...

There are some very good reasons there are regulations, etc. about stuff like power cords.  And it does matter - I still have vivid memories of a couple of guys scrambling down a stairway yelling "Fire!" many, many years ago and what caused that is probably not much different than your creation.  It's really, really just not worth that.


Well, mine was more than just theory. It’s also legal liability.

Imaging trying to explain to a judge that the 4 house fire you caused should not have happened because you used 4 network cables braided together, and that you HAD to do it because your DAC was too bright otherwise...

I woudln't want to be in that courtroom at all.

Use only cables approved for use as power cords or get a hobby that doesn't risk your life and that of others.

Best,


E
You guys are great. Truly. Erik, I appreciate your no BS attitude. I’m curious, though, why other diy power cable threads haven’t gotten this rawkus. Is it the cat5e cable, or my edgy headline? Because I’ve made other power cables and mentioned it in other threads, as have others, and this is the first talk I’ve heard of houses burning down and liability and such. I do realize I started the house burning down talk.. :-)

I did just find, buried in the NEC, that UL listed communications cables are rated to, at minimum, 300v. 24awg solid copper can handle .6 amps. I have 24 strands per conductor. As long as I terminated everything well, in terms of electrical theory, is there a safety problem? That’s my real question. Not liability. I understand that part..
Here’s a test for you - go to Home Depot and buy what ever length of cord you need replace your CAT5 cable with this
http://m.homedepot.com/p/Southwire-10-3-SOOW-Black-600V-By-the-Foot-55809799/204632922
Its 10 gauge too so you will compare apples to apples, then let us know if you - truly - hear any difference. This wire is designed for what you use it for.

Good listening

Peter
As a retired insurance manager, I can tell you that only intentionally set fires are denied, i.e. arson. There is no exclusion for stupidity. For example, you leave a frying pan unattended on the burner, house catches fire, covered loss.

To address your point about 24 x 0.6 ~ 15 (amps), and braiding together,  the current carrying capacity of multiples depends on their exact physical relationship. That is, if insulated wires are close together, they will not be able to radiate heat as efficiently as if they were separated. Then wires might get hot. Hot (copper) conductors have higher resistance. This has the potential to create a positive feedback loop, and we are back to the potential for HF.

How much current does each monoblock pull? (on the rear of the amp somewhere it will say "120V xxxW" W being the power in watts the power supply pulls at maximum draw, not the rated speaker power output.) Then divide watts by 120 to get the current draw.

Also, there's the fuse rating of each monoblock. Let's say it's 8 Amps. Then you can use wire that's rated slightly higher than that, say 10 Amps. 14-Gauge wire is rated at 15A, so this would be about the minimum gauge for this example.

I can't guarantee that you won't have problems with your homemade PC, but if your wire is well-terminated (won't come loose/disconnected), and doesn't run hot, I don't see a problem with it. But if it gets moved around much/bent, some of the small wires of the CAT cable could break, which would put more heat strain on the remaining wires because they're still connected, and the same current has to go through less wires.

Like was said above, the ideal thing is to get some proper power cord to be sure.
Yes, calculations and specs must be factored.  Terry9 nailed the concern about quality of the insulation and the quality of the mechanical wire connections.  Have you ever felt a really cheap extension cord that was carrying a large electrical load over an extended period of time?  The insulation is warm to the touch.  If the load is beyond the cord's safety specs, it is actually hot to the touch.  A serious safety hazard is imminent!   You can try the same thing with your DIY pc's.   A simple un-scientific test is to create as much load on the pc's as possible by pushing the amps to play loud, dynamic passages for a while.   Are they warm to the touch?  If so, dump them.  They should be room temperature.
So far, they run completely cool..
@pbnaudio those (home depot) are the very cords I used when I first made my own cords a year and a half ago. All the other cords I've made since then have sounded better. But your signalcables link got me curious, so I may buy one, just to compare. 
@steakster @joeylawn36111 I'll check those specs later. Good point about twisted pairs not being able to radiate heat as well as an individual strands. Still, I've played the stereo loudly and none of my diy PCs run even remotely warm. Including the cat 5 one.
@ericsch thanks for the clarification. I guess if insurance companies could get out of paying claims due to stupidity, they probably wouldn't pay many claims at all..
Post removed 
The problem with CAT5 cable - it is not rated for mains use - period!!!

As another poster commented - the insulation needs to be rated to mains cable levels. i.e. capable of withstanding 600v at 200 celsius

CAT5 is OK for speaker cables or IC’s, but it should NEVER use for mains use!

Granted - a pre-amp drawers low current under normal operating conditions, but the wires used in mains cables are rated for conditions that exist under a fault condition (i.e. short circuit).

And as other posters have noted above - Insurance companies will not pay if YOUR CABLE is determined to be the caused of a fire.

Regards...
Good point, williewonka - the insulation isn't really up to snuff for 120VAC. 

Bottom line = Using proper mains cable rated for line voltage - almost zero chance of a problem (properly wired, of course)

- Using CAT5 cable - a small, but significant risk that definately(sp?) above zero.
I would listen to the advice above. I am an avid DIY guy also building all my own power cords etc... Cat5 is not a good option. 
I’m not dead yet.. ;-)

Wiliewonka - cat 5 plenum cable insulation is Teflon and is good to 200* C. Cat 5 is also rated to 300v. Not 600, but well above 120.
Todd - As far as I understand even cables with the plenum jacket still have typical shielding around the inner conductors - that's the real problem.
toddverrone OP 102 posts                                                02-17-2017 10:04pm

I’m not dead yet.. ;-)

Wiliewonka - cat 5 plenum cable insulation is Teflon and is good to 200* C. Cat 5 is also rated to 300v. Not 600, but well above 120.

//

Actually they make a shielded 600V insulation rated twisted 4 pair cable.
The insulation rating is not for the copper conductors of the twisted pair cable. It’s so the cable can be installed in the same cable assembly or raceway, like a Cable Tray, with other conductors. Or in an MCC, (Motor Control Center) cabinet with power cables. NEC code says the cables shall have an insulation voltage rating not less than the highest voltage of other wires or cables in the same raceway, cabinet, or cable assembly.
Benefits of Using Belden DataTuff Category 5e 600V AWM-Rated CablesBelden provides two Industrial Ethernet Category 5e cables designed specifically for superior electrical performance and outstanding noise immunity. The Belden DataTuff 4-pair shielded cables carry a 600V AWM rating which makes them approved for use in listed MCCs and switch gear, and they feature Belden’s patented Bonded-Pair technology. While these cables have the design and certifica-tions that make them ideal for MCC and switch gear applications, they can also be used for more tradi-tional Ethernet applications. They are not, however, intended for 600V power delivery.
https://www.belden.com/docs/upload/NP314.pdf

NOTE: They ARE NOT, however, intended for 600V power delivery.

//

A twisted 4 pair cable is not designed/manufactured to be used as a mains power cord. It can be used for low current power application. Example would be POE (Power Over Ethernet) LED lighting. There are other power limited examples.
You can parallel all the conductors together as you want but it still does not increase the maximum allowable current rating of the twisted pair cable per UL or NEC.

As far as I know the outer jacket of the cable sole purpose is to hold the lay/geometry of 4 pairs in place. Yes it can be PVC or plenum rated for where it can be used to meet NEC code. Changing the lay/geometry of the 4 pairs will change the design characteristics of the cable. The cable is made in non shielded and shielded.

//

I decided to make a PC out of cat 5 plenum cable. I kept it in its blue sleeve (containing 4 twisted pairs) and then I braided 3 lengths together for each conductor. I then took those three braids and braided them. What I have sounds incredible and I’m fairly confident that it is safe electrically.
If you are hell bent on using cat 5e for a power cord I would suggest you use some type of recognized insulating sleeve material to cover the paralleled groups of the hot and neutral conductors prior to braiding them together. Teflon has zero physical abuse properties. I know of no UL Listed aftermarket power cord that uses Teflon for the outer insulation covering the current carrying line conductors.
When bent too sharply it stretches the outer side of the bend making it even thinner than it already is. With an approved outer insulating sleeve material the entire length of the cable you will insure there is no chance of a HOT line to neutral or Hot Line to equipment ground short or worse arcing. Arcing is the main cause of electrical fires.

It’s not the connected load of the piece of audio equipment you should be worried about. It’s the available short circuit/ground fault power your branch circuit and electrical panel can deliver.
And just because you paralleled a bunch of insulated 24 gauge copper wires together does nothing for just a few that might fault, for what ever reason, from hot to neutral, or hot to equipment ground. Only those few are at play in the faulted circuit.

Safety electrical standards and codes are written for the what if happens.


The actual insulation around the wire itself is Teflon... I think the blue outer sleeve is PVC.

@jea48 that was a beautiful post. Points taken. I have the twisted pairs still in the blue outer sleeve and all 4 twisted pairs are used in parallel, I’m not running hot and neutral or ground in the same blue outer sleeve. The three lengths of cat5 for ground are all still in their outer sleeve, then braided. Likewise for live and neutral. It’s rather rugged. There’s  no chance they’ll short.. The only thing I could see happen would be if it was flexed a lot and very acutely. Then, if a few wires broke, the remaining wires on that pole could get hot and cause problems. 

That said, this was just meant to be an experiment to see what I think about multiple solid gauge conductors, separately insulated and braided together to form larger conductors. I’ll probably do something similar out of 20 or 18 gauge 600v wire. Any recommendations? OCC or the like would be nice.
Todd - I buy the Mil-Spec wire form my power cables from Take Five Audio...

https://www.takefiveaudio.com/categories/100-deep-cryo-treated-cablewire

Email Take Five to ensure the insulation is up to code

Here's the design for my power cables...
http://image99.net/blog/files/be8de0c383c5434907610d6b55049e69-75.html

Regards - Steve
@williewonka I've already got two of your helix design power cords hooked up to my monoblocks. I ended up using the yarbo 9000 series cable from vt4c as the donor cable for the main conductor. They sound great.
The actual insulation around the wire itself is Teflon... I think the blue outer sleeve is PVC.
Not from my experience. The outer jacket is Teflon and the insulation around the wire is PVC. It is the outer jacket of the cable that is plenum rated.

In the case of Belden they stopped using Teflon for the outer jacket of their plenum rated cable years ago. Belden developed their own outer jacket material. It is called Flamarrest®.
Outer Jacket Trade Name Outer Jacket Material
Flamarrest® LS PVC - Low Smoke Polyvinyl Chloride

//

That said, this was just meant to be an experiment to see what I think about multiple solid gauge conductors, separately insulated and braided together to form larger conductors. I’ll probably do something similar out of 20 or 18 gauge 600v wire. Any recommendations? OCC or the like would be nice.

There are quite a few cable company manufactures that make after market power cords for audio equipment that use multiple paralleled individually insulated solid core wire for each of the two current carrying conductors of their cords.

Examples of aftermarket power cords using multiple insulated solid core conductors.

PS Audio
http://www.audioadvisor.com/prodinfo.asp?number=PSPWAC5

Pangea Audio AC 9SE MKII Signature Power Cable
http://www.audioadvisor.com/prodinfo.asp?number=PGAC9S2

Audioquest
https://www.crutchfield.com/S-wi4RnpruA6y/p_703NRG23F/AudioQuest-NRG-2-3-ft.html

Shunyata
METALS AND CONDUCTORSCCC
- COMPUTER CONTROLLED CRYOGENICSPROPRIETARY PROCESSESVTX™
 ConductorsShunyata Research’s exclusive VTX™ conductors are made in the shape of virtual tubes. The core of the conductor is completely hollow minimizing skin effects and random eddy currents. They are produced using OFE Alloy-101

http://www.shunyata.com/images/technical_features/pdfs/pwr_tech_201509.pdf
Not sure of their actual construction design. I couldn’t find any actual pictures.

Note in all cases the outer protective insulation covering the hot and neutral conductors/wires is PVC and rated for mains power handling applications.


Todd - thanks for the feedback :-)

It’s always good to get feedback about what components they work well with.

I found their benefits were more noticeable on the components with "less robust" power supplies - such as source components.

By contrast, the benefits on my amp (with a large transformer) were more subtle in nature - such as more clarity in the more delicate venue reverberations.

Cheers
At least use Cat6, lol. Seriously though, Cat5 type cable is specifically designed for LOW VOLTAGE applications. You're playing with fire here.
I promise, if you do the research you can confirm, cat 5 that is UL listed is rated to 300v
@williewonka I was using them with a dared mc 7p pre and a class D crown xls1500. Now they're powering 2 Ghent audio 500w class D monoblocks. I find with class D that the heavier gauge conductor makes a big difference in sonic performance, especially bass control. The helix cables I made have 10 gauge main conductors..
@jea48 check this: http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet393

That is the wire I used. The outer jacket is high temp smokeless PVC and the individual wire insulator is FEP or what is commonly referred to as Teflon. I promise I did my homework
You should use it. You're confident you've done your homework and feel that no one has raised any good arguments that it's unsafe. So why keep beating this horse?
I have been. But it has been a good discussion and it's very interesting, the reactions I got. I keep responding with info to make this thread more useful to someone in the future. I learned a lot from threads like this..
toddverrone OP 121 posts                                             02-20-20172:26pm

@jea48
check this:

http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet393

That is the wire I used. The outer jacket is high temp smokeless PVC and the individual wire insulator is FEP or what is commonly referred to as Teflon. I promise I did my homework
It’s good the outer jacket of the cable is PVC . At least for the way you are using the cable it gives a little better physical abuse protection.

Yes, it says the insulation cover for each 24 gauge wire is FEP. Though if you scroll down the page it says the insulation is thermoplastic, which is PVC. I wonder if it is thermoplastic with a layer of Teflon over that?

toddverrone OP 121 posts                                      02-20-2017 10:39am

I promise, if you do the research you can confirm, cat 5 that is UL listed is rated to 300v

Yes, you are correct. But at very low amperage, rated in ma. Example, the ringer voltage on a telco phone system. The voltage on the ringer circuit can averages around 90 volts AC. It can go as high as 140Vac, possibly 150Vac. But the current is very low in the ma range. The circuit is also fuse protected which limits the current.

Again the cat5e cable was never designed/tested/manufactured/UL Listed to be used as a mains 120Vac power cord. If for what ever reason the cord faulted the current available from your electrical panel could be in the hundreds of amps before the branch circuit breaker could react and hopefully trip open breaking the fault. Will all the paralleled #24 gauge wires survive the event? What limiting fuse protection do you have to protect the parallel 24 gauge wire of the power cord?
If the fault is an arcing fault the breaker will never trip as long as the continuous current draw is below the breaker handle rating. Of course the same is true for any power cord. One reason for NEC code AFCI (Arc Fault Circuit Interrupter) branch circuit protection.

Bottom line..... You feel safe with the power cord you have assembled. The PVC outer jacket on the cat5e helps. I personally would not build a power cord using cat5e data cable. I would also not recommend anyone reading this thread do so either.
.



Todd WRT...

@williewonka I was using them with a dared mc 7p pre and a class D crown xls1500. 

Did you happen to observe any drop in operating  temperature of the crown xls1500 whilst using the Helix power cables?

My solid state source components ran noticeably cooler (i.e. by a few degrees) when connected with both Helix power cables and IC's.

e.g. My DAC dropped by at least 10 degrees Celsius - i.e. from quites warm to the touch down to room temperature.

Cheers

@jea48 I’ll join you in not recommending anyone use bundled cat 5 cables as PCs. I’m happy with with them, but am aware of their possible safety issues and have taken steps to mitigate them. Despite that, this isn’t a cord that can take the abuse a regular PC can.

@williewonka I can’t say my xls ran any cooler because it’s class D. It ran so cool, the fan hardly ever kicked on, even with the stock cord and it was never even remotely warm in any place I could touch. I saw a post in the tech talk section that made me think of you though. It was a PDF talking about power distortion in an industrial setting and how to mitigate it. One thing it mentioned was that, for industrial switch mode power supplies, having the neutral conductor at least 1.7 times the size of the hot conductor reduced the noise dramatically. Your helix design has the neutral conductor twice as big as the hot, as I’m sure you know..
Not sure if industrial switching power supplies behave like home audio, but interesting none the less.