So here is an interesting question  - like to hear some of the views on this .

I need to connect my car charger permanently - it is rated to be run from a 16 A plug (3kw). It typically run overnight to charge the car and I find that the plug heats up.   I want to install it on a dedicated circuit via a "welding plug " - 32 A rated plug to connect the charger . This will be connected on a dedicated circuit - eg like a stove connection . Will be using 4 mm house wire .

So here is the question : I had an installation a while back where I made up a solar 4mm pair with a earth wire and after running the bundle to the inverter I cut the extra part off . So now I have a live , neutral and earth bundle that will exactly fit as the supply for the charger . So can I run AC over a Solar cable ?

My take on this : You usually see the comments from the other side - don't run house wire as a dc clable - lower voltage rating , PVC vs XPLC etc . and I agree, but this is now the other way and normally I would just use gp wire but waist not want not ? Effectively a solar cable is a superior cable - current wise it is fine , it is fire rated , it is high voltage rated etc.  The only difference is that it is stranded vs 4mm2 GP wire has 7 strands , it is more expensive, but I have this made up piece that I will not use on a site and a there  currently  is also a shortage for gp wire - so would you use it ? 

 

 

 

18 minutes ago, 1ougat said:

So here is an interesting question  - like to hear some of the views on this .

I need to connect my car charger permanently - it is rated to be run from a 16 A plug (3kw). It typically run overnight to charge the car and I find that the plug heats up.   I want to install it on a dedicated circuit via a "welding plug " - 32 A rated plug to connect the charger . This will be connected on a dedicated circuit - eg like a stove connection . Will be using 4 mm house wire .

So here is the question : I had an installation a while back where I made up a solar 4mm pair with a earth wire and after running the bundle to the inverter I cut the extra part off . So now I have a live , neutral and earth bundle that will exactly fit as the supply for the charger . So can I run AC over a Solar cable ?

My take on this : You usually see the comments from the other side - don't run house wire as a dc clable - lower voltage rating , PVC vs XPLC etc . and I agree, but this is now the other way and normally I would just use gp wire but waist not want not ? Effectively a solar cable is a superior cable - current wise it is fine , it is fire rated , it is high voltage rated etc.  The only difference is that it is stranded vs 4mm2 GP wire has 7 strands , it is more expensive, but I have this made up piece that I will not use on a site and a there  currently  is also a shortage for gp wire - so would you use it ? 

 

 

 

This sounds like never use a piece of 4sq mm PVC AC house wire to power a 1W LED light because its DC. 

The copper does not know you are using it on AC or DC and to explode or heat up if used on the wrong power. 

If the insulation is of a proper rating then no problem. Yes you have indicated the fire side which must be considered in the specific application. 

Let's hear from those in the know. 

12 minutes ago, Scorp007 said:

This sounds like never use a piece of 4sq mm PVC AC house wire to power a 1W LED light because its DC. 

The copper does not know you are using it on AC or DC and to explode or heat up if used on the wrong power. 

If the insulation is of a proper rating then no problem. Yes you have indicated the fire side which must be considered in the specific application. 

Let's hear from those in the know. 

consider the following whether copper 'knows' its carrying AC or DC

 

Wire that carries AC typically has more strands compared to that used for DC

I believe this has something to do with the magnetic field around a conductor with AC current, causing the resistance to be higher in the center of the copper strand and thus electrons tend to move along the surface. In contrast, current in DC tends to flow in the middle of the conductor

This is why AC cable tends to have more strands to increase the surface area and mitigate this effect

 

EDIT: https://en.wikipedia.org/wiki/Skin_effect

Edited February 4, 20233 yr by jeddles

32 minutes ago, jeddles said:

consider the following whether copper 'knows' its carrying AC or DC

 

Wire that carries AC typically has more strands compared to that used for DC

I believe this has something to do with the magnetic field around a conductor with AC current, causing the resistance to be higher in the center of the copper strand and thus electrons tend to move along the surface. In contrast, current in DC tends to flow in the middle of the conductor

This is why AC cable tends to have more strands to increase the surface area and mitigate this effect

 

EDIT: https://en.wikipedia.org/wiki/Skin_effect

The way I see it we just have to look at real power. Look at overhead power lines which run on AC and DC and the same conductors are used. We talk of 765kV and even higher. What is good at this voltage should be good at 600V.

One will find no reference to AC or DC only the current carrying capacity. 

But we know thanks to the Internet each member is a specialist. 

Edited February 4, 20233 yr by Scorp007

On face value I would like to think that the choice of multistrand pv cable has mostly to do with the 'free' wiring nature of routing copper from the panel. It allows the cable to hang or lie or ease up around the bend under the panel.flexibility. 

Edited February 4, 20233 yr by BritishRacingGreen

1 hour ago, 1ougat said:

don't run house wire as a dc clable - lower voltage rating , PVC vs XPLC etc

really? I will run house wiring as DC cable, but one must take into account the fairly thick few strand that are there are not intended to be run as a flexible cable, but installed in a conduit once and the not be moved again... ( if I remember correctly a conduit run is only supposed to have a maximum of 2 90° bends, else extra inspection joins are supposed to be installed etc.... but I could be mistaken on this, this refers to AC house wiring anyway)

if you intend to run this wire for HT DC, so 400V or more for DC applications, then double check what the insulation Voltage rating is and ensure you're well withing limits... as for flexible many stranded cable used elsewere, it usually is this many strands to make it more flexible and easier to install and possibly move around even... DC would be happiest with one solid conductor, but this is pretty unwieldy and would not really bend all that easy and thus is mostly a no-no...

as for the skin effect quoters, at 50/60Hz its more than 8mm, and thus a single strand of 17mm diameter copper/aluminium rod would still not show up the skin effect for mains, so come up to UHF and SHF and yebo yes, even on HF, 3.5MHz to 3.8MHz the discussion was there recently on the AWA net about Magnetic loop antennas and in this scenario where the skin effect would allow you to use a 110mm diameter plumbing pipe with aluminium foil on the outside to effectively end up with a 110mm diameter conductor, since even if it were 110mm solid conductor, probably only the outer 5/100th of a mm or 50µm would be used and the higher you go the less material thickness would be needed, but this is academic down at audio frequencies, you would not likely get near the skin effect wasting some of your conductor...

for all intents and purposes DC and 50Hz in a conductor are indistinguishable from each other as far as the depth of the conductor used by the electron flow...

getting back to...

2 hours ago, 1ougat said:

So can I run AC over a Solar cable ?

yes, no reason not to, this cable is probably specced for 600V or 1000V even, so at 240V it will do no better or worse than any proposed cable that fits the bill...

I think the bottom line and answer to the social media debate about AC-DC is to provide the spec from any manufacturer that indicates it may only be used for AC or DC. 

This appies to ANY of the cables that we tend to use. Further even a 300/500V cable is tested to 2250V.

As Kalahari said. Go ahead and use the DC 😀 cable. Solar cable has a higher spec and better suited to the conditions they can be exposed to. 

Well - I went ahead and did it 🙂

Agree with the sentiments expressed - current is current so the current rating is more important in this case . The insulation is supperior to the normal PVC so good on this front and the multistranded nature of the DC cable is to cater for more movement so ok on that front also . The colours is also ok - So that was also my assesment . Thanks everyone .