Is the market flooded with fake dangerous solar cable

[Robint]

WOW TT and I thought I was struggling with a crock of schwepps. Industry Standard - where is this generally accepted? And Quora is one of those Opinionator boards, mostly WOS


Your 12V supplier is equally full of misleading BS.
The actual csa of 10AWG is 5.26mm2, 4.5mm2 is nearer 11AWG, so short changed there
I can understand that the criteria for cable is the ohms/km which the manufacturer has to meet. How the cable is stranded is up to factory conditions and is specified as nominal csa.
But copper is what it is and AFAIK plain industrial copper has a fixed resistivity rho = 1.68E10-8 ohm-m. I could live with say +/-2.5%, material tolerance but we are seeing big discrepancies here


AFAIK we expect 6mm2 good for 70 and 4mm2 ok for 50A cos it has high temp silicon sheath good for 90C



Domestic cable has a table of standard ratings ( and derating according to installation free air, trunking, number of cores, ambient temp etc. Industry doesnt mess with those. You buy 2.5mm2 cable that what you get not 2mm2

[wholybee]

Did you actually count the strands and measure the diameter of each strand?

[skipperpete]

Thank you TinTin for providing accurate and useful information.

[Robint]

Originally Posted by wholybee

Did you actually count the strands and measure the diameter of each strand?

Yes I counted the strands, 84 and I measure a dozen or so with a Mitotuyo digi calipers and they were all the same 0.22mm dia
I seem to have opened Pandora's box.


I guess the maker measures ohms/km on the drum. Measuring short lengths (mine 15m) is difficult as you are dealing with ca 20milli ohms and needs special equipment. I will do another 4 wire current reading now Ive pit ring term on both ends


Report tests shortly

[Robint]

Originally Posted by Tin Tin

I bought some tinned marine cable the other day. Its "nominal" size was 6mm (10AWG) - the actual cross sectional area was 4.5mm2 . So then I checked a bit more and apparently there are industry naming conventions. See this website for 10AWG and look at the asterisk notes. https://www.12volt.com.au/6mm-10awg-...8-amp-4.5mm-so...

TT Light bulb moment - this Industry standard refers to the US habit of referring to csa by circular mils ie pi/4*dia (ca 0.78d) so 6*0.78 = ca 4.5mm2.


eg 1 circ mil of area has a dia of 1mm (3.142*1/4 ) = 0.78*mm2

[Jammer]

Originally Posted by Robint

Ahoy there.


Has anyone come across XLPE Solar cables as used on panels which turn out to be falsely represented to the buyer. I my case I received (a short length) of what looked like a genuine TUV certified item but on closer measurement had a core size of ca 4mm2 (84 x 0.25mm)rather than the 6mm2 I order and what was printed on the cable sheath? I had another sample from a different source and this was 3.12mm2 ie 50% below the listed csa and ampacity (ca 40 A vs 70A)

This would be a difference of 2 thousandths of an inch (0.002") per strand which is difficult to measure accurately even with a micrometer, as the copper is easily crushed.


I would encourage you to check your measurements carefully and compare things like the weight of the conductor per foot -- which is easier to measure accurately -- before getting too wound up.

[Robint]

Indeed J
Quite right
I was so astonished at what I found, I trawled around first to see If anyone else has found this. So I have been cross checking with different measurement methods. Its difficult to measure 0.22mm dia wire, but I do have a precision 5 digital calipers by Mitutuyo - a tool room standard Absolute gauge. I will do some more measurement today and post.


Found some interesting info on the dark arts of making stranded cable - not as simple as it might seem. The circle packing problem within a minimal circumference is a big maths problem not fully solved (but has numerical approximation solutions. It stewed my plums
BTW I might have some useful pix but these cant be posted within this window, should I set up a members galler and post there ref from here?

[OneBoatman]

Dangerous maybe, it is sometimes difficult but one should always exercise care in making quality, safety, and purpose decisions when it come to the things we choose to put aboard our boats. Even on land, I found that I usually end up in a better place if I do not buy anything I expect to last or that threatens safety from China. As for flooded, it boils down to what you are willing to spend, time invested as homework, and what's available since they are indeed such a huge part of the World's electric supply chain. More and more this limits our choice. Chinese companies for the most part do a great job at making things that look similar to what we had last time and what expect will do the job. Experience tells us it sometimes actually works, unfortunately we soon re-learn that the shortcuts they take in manufacturing, often not readily apparent, will more often than not leave us disappointed in our decision to try and save money.

[wgerstmyer]

Tin Tin
That is some amazing text! As we architects would say the code seems to suggest it is ok to have a performance based requirement (much tougher to confirm as an end user) versus in prior requirements where “size is size” and confirmation of the products was a snap.

[rwaldrop13]

Originally Posted by Robint

Ahoy there.


Has anyone come across XLPE Solar cables as used on panels which turn out to be falsely represented to the buyer. I my case I received (a short length) of what looked like a genuine TUV certified item but on closer measurement had a core size of ca 4mm2 (84 x 0.25mm)rather than the 6mm2 I order and what was printed on the cable sheath? I had another sample from a different source and this was 3.12mm2 ie 50% below the listed csa and ampacity (ca 40 A vs 70A)

While not with solar cables I have become very distrustful of Amazon reviews. That said, I tend to watch YouTubers like Trying Not to Sink and podcasts like Boat Galley for product recommendations.

[Icarus]

Originally Posted by Robint

Thanx Gord


FYI I would not be troubling this board if I had gone out and sourced a cheap charlie unbranded product. As the saying goes "you get what you pay for"]The samples I received were branded as per the TUV spec completed with maker's ID and refs and material specs and its csa 6mm2.So at first sight you think you are buying a correct cable, only to find on measurement that it is 84x0.22mm dia wire strands rather than 84 x 0.30mm dia strands. This means 3.12mm2 vs 6mm2 - thats a very big difference - not 70A but 35A ampacity.It may be stateside you dont have this type of fraud fake products, counterfeit issues? Just checking if anyone has heard of this.

China has not got stringent production codes as one would assume other countries like the EU or US would have. ( I presume your panels are made in China?)
When in daub just change the cables from the solar panels to your requirements.
I know its a pain

[Robint]

Originally Posted by Icarus

China has not got stringent production codes as one would assume other countries like the EU or US would have. ( I presume your panels are made in China?)
When in daub just change the cables from the solar panels to your requirements.
I know its a pain

Maybe you are missing my point here, my OP was to alert Members to the possibility that what they are buying (or allowing an installer to use) may be fraudulently labelled.

This is not about Chinese codes - its about fake cable made to look as though its produced according to EU standards and it then turns out to be significantly undersized. OBTW one of my fakes was made in the Middle East from a well known factory - 4mm2 cable deliberately labelled as 6mm2



Is'nt it better to be an informed buyer than having to rip out your unsafe cables

[Robint]

I doesnt get any better as I dig deeper. I now have 4 samples of potentially fake cables sold as 6mm2 but sized ca 4mm2, The latest one was stamped as made by a well known US cable maker, I am sending him a sample. Clearly I am not suggesting the Big Corps are not responsible for this fraudulent activity but there seems to be some dirty business going on here as I am gathering evidence.


I doubt if installers will disclose their experiences here, I am just hoping that some whistle blower will show up. I am only a lone voice so far.

[Wotname]

Originally Posted by Robint

...... Clearly I am not suggesting the Big Corps are not responsible for this fraudulent activity but there seems to be some dirty business going on here as I am gathering evidence....

Presumably the double negative was unintentional. As written, it is suggestive that Big Corps are responsible for the fraud. I don't think you intended that.

Hopefully from the samples they will be able to determine what is going on. Keep up the good work.

[GordMay]

FWIW:
Cable diameter to circle cross-sectional area and vice versa
➥ Cross-sectional area to diameter conversion circle intersection cross section diameter electric cable conductor formula wire diameter and wiring and calculation cross section AGW American Wire Gauge thick area of a solid wire formula conductivity res

A 6.0 mm2 Cross Section wire has a Conductor Diameter of 2.8 mm Nominal [2.764mm actual].