[FraGGleR]

I have some CL3 rated speaker wire that I wanted to use to make an AC power cord.  The speaker wire is discontinued and I haven't been able to find the specifications on what voltage rating the polyethylene dielectric has.   Doing some research, CL3 rated wires are supposed to handle up to 300V.  Does this mean that the wires themselves are rated for up to 300V or just the outer PVC jacket?  Asked another way, if the speaker wire is rated as CL3, could I use it as the basis of an AC power cord?

 

[superjawes]

I think that, as far as voltage is concerned, you are going to have to know the insulation on the individual wires (unless you splice them together, but I'll get to that). I do not know whether the 300V relates to the individual insulation or the outer jacket.

However, the real limiting factor here isn't going to be voltage, but the current you need to draw. The wire gauge is going to determine whether the wire works, or more accurately, whether or not your copper is going to melt. I do see different gauge wires when searching for "CL3 Rated Wire." And even if the wire doesn't melt, going with too low a gauge is going to A) make for a hot (temperature wise) wire and B) could result in a nontrivial voltage drop between the outlet and your device.

Now you do get one freebie, though. You could splice both wires together at the terminal(s) and get an effective gauge increase (number decrease, but larger effective wire size), and if you put two pairs (so four total wires) in a new jacket, the final wire could be safer, and it would sidestep the voltage confusion. You will still need to make sure that you aren't overloading the wires from a current perspective.

 

[FraGGleR]

Thanks for the input. I'm not worried too much about the current, as it is 16ga wire and the component won't be drawing more than a few amps. So really the question is about whether or not the individual wires can handle 120 or so VAC. Hoping that some who understands the CL ratings might be able to help.

Alternatively, is there a safe way to test the wire?

 

[Speedskater]

Note that they have the same inwall fire safety requirements as Article 3 AC power wires and cables. But the reason for Class CL2 and CL3 cables is to lower costs.  They are reduced requirement cables.  They are not designed to carry high current 120/240V power. 

 

[KimLaroux]

CL3 just means it's rated to be used in-wall. But for speakers only.
 
It'll work as a power cable, many people use cheap speaker wire for lamps in their living rooms. Just don't do it. It's playing with fire - literally. 
 
http://www.audioholics.com/audio-video-cables/understanding-in-wall-speaker-video-and-audio-cable-ratings

 

[FraGGleR]

Most secondary resources seem to reduce the definition to just being in wall rated.  I have dug deeper, and while I haven't interpreted anything to be definitive for me, I have a feeling that the CL ratings are more for the protective outer sheath rather than the wire itself.  I feel like it would work fine, but I'm not going to risk a fire.  I have some other wire that has a XLPE dielectric rated up to 300V so I will use that to be safe.
 
Thanks everyone.

 

[Chris J]

That cable doesn't sound like it's UL approved for use as AC Power Cable, if I'm not mistaken.
If it's not UL approved as AC Power Cable, then don't use it.

 

[65535]

Cable's cheap, though the Class 3 rating indicates it's good for 300V it isn't the proper cable for your intended use. Cable is cheap, pick up some SJOOW or similar 2-3 conductor wire and call it a day.

 

[Chris J]

Cable's cheap, though the Class 3 rating indicates it's good for 300V it isn't the proper cable for your intended use. Cable is cheap, pick up some SJOOW or similar 2-3 conductor wire and call it a day.

Sorry for this, no offence meant, but SJOOW is not rated for in wall use.
At least CSA doesn't rate it for in wall use...

 

[65535]

He want's to make a power cable which should not be in-wall.

 

[Chris J]

He want's to make a power cable which should not be in-wall.

 


Duh!
You are absolutely correct!
He should stick with your SJOOW or equivalent.

 

[FraGGleR]

Cable's cheap, though the Class 3 rating indicates it's good for 300V it isn't the proper cable for your intended use. Cable is cheap, pick up some SJOOW or similar 2-3 conductor wire and call it a day.

If it is rated to 300V and is of large enough gauge to handle the current necessary, does it matter if it wasn't purpose built as power cable?

And for others who have chimed in, CL ratings aren't fire ratings per se. They have to do with voltage handled to prevent arcing between adjacent cables (which can cause fires). That is what I have gotten reading more about the spec. What isn't clear is whether or not that applies to just the outer jacket or also the internal wires.

I have already decided to not use the wire because of this doubt, but it would be good to get a real answer to fill in the knowledge gap.

 

[65535]

It's rated for 300V on the conductors, however it's an in-wall cable which means it's for permanent installation. The wire isn't intended for repeated flexing like a power cable is.