In case you weren’t aware, here’s one of the many ways unregulated electronics bought online can be dangerous. A regulation Australian IEC cable must have 3x 0.75mm²+ double-insulated stranded copper conductors. This cable appears to meet that requirement at first glance — it’s marked that way on the outside, and cutting in, the PVC colours are wrong but otherwise appear okay.

But then, scrape some of the copper, and it suddenly turns silver. It’s CCA, or Copper-Clad Aluminium. A sneaky and cheap but worse conductor. The aluminium holds up much worse to corrosion and bending, and will crumble to powder inside the cables over time. Through this process it will increase its resistance, turning into a fire-starter. Very dangerous and invisible without destroying the cable to examine it.

Visible in the background is the non-compliant angled-pin plug which is common in China, and fits into Australian power points, but is missing several key safety features (active & neutral sheathing, distance to edge of plug, cord faces wrong direction). It also turns out to have plated aluminium pins, which is super dodgy too!

@s0 Wow, I have one of those cables where the cord comes out in the wrong direction, and I just thought it was someone's quirky design choice. Came with something ages ago, I forget what. Guess I'll retire that one.

@mike their power points commonly look like this, mounted with the earth pin at the top instead. It’s safer for things falling in from above (hence the lack of pin sheathing) but worse for flooding. There are also slight dimensional differences.

@s0 British plugs are objectively the best (unless you step on one), they're rock solid and there's a fuse inside the plug

There's also a mechanism of some kind inside the socket to stop e.g. kids sticking stuff in the live hole, it only releases and allows contact if you insert an actual plug

@ak I would argue Australian/NZ ones are better.
fuses in plugs aren't really helpful these days when great majority of devices pull small loads, only a few pull high loads and power boards/house wiring are required to come with overload protection. This prevents the case of end user replacing a plug fuse with a bigger one to stop tripping.
The same plug style comes in 10A, 15A, 20A, 25A and 32A keyed variants, all of which fit into higher-rated sockets, which makes AV/Theatre industry electricals a breeze compared to America & Europe.
Both have sheathed active & neutral pins. Shutters being mandatory is one thing that is quite good about British ones but does decrease the usable/safe linespan of GPOs to the mechanical limit of the shutter mechanism. More failure points.

@s0 @ak

Many UK theatre light installations still use /old/ British standard round pin plug (BS 546), rated at 6A or 16A (there are two different sizes, 16A is most common) as lanterns are often high up in the grid so dealing with opened plug top fuses is a hassle (and the dimmer circuit is protected anyway); for higher current (32A and above) BS4343 (CEEform) connectors are deployed (although most smaller setups are all LED nowadays so use way less current than before)

@vfrmedia @ak ceeform are good for when waterproof connections are needed but pants otherwise. Way oversized and a pain to plug & unplug for their ratings.

@s0 Having devices be low power these days is an argument *for* fuses in plugs. If the final circuit is protected by, say, a 20A breaker then 3A devices need either their own protection or leads which are capable of sustaining 20A partial shorts, which seems unnecessary.

(OK, it's more complicated than that because of the trip times of breakers and the need to have a big enough PE to limit case voltages but the principle's there.)


@s0 somewhere I have a Chinese cable with the usual grounded three pin computer Plug on one side and a two pin Euro plug on the other. Wire cores are not even half as thick as the ones you show. At least the act as fuse then, hopefully...

@s0 Did you just say plated Aluminium? Excuse me but WTF?!

What is exactly underneath that Aluminium, which in modern times, is one of the cheapest metals known to man despite being so 'energy dense'!

@VK3VKK @s0 This is a chinese power chord. It's made of chinesium.

@Infoseepage @s0 Communication cables used Al conductors of 0.52 mm diameter to replicate the conductivity of 0.4 mm Cu conductors. The Al cables were fragile, didn’t work properly in the connector interface with Cu cables and the Al ones didn’t cope well in conduits near roads with heavy vehicular traffic. In my Telstra career my sole exposure to Al cables was when I chopped up a ute-load of damaged cable with an axe.

@s0 sounds terrible! How does one report “fake compliance” like this when you come across it? (In Australia)

@stragu if it’s sold in a physical shop or an online shop located in Australia, you report it to the department of fair trade. If it’s bought online from overseas, there’s no ability to regulate, which is how most of these end up in the country.

@kravietz at least there is/was an argument to be made that permanent wiring isn't as much of an issue with constant bending, and larger strands won't corrode and fall apart as much. But the issues with junctions between dissimilar metals certainly are enough danger on their own.

@s0 @kravietz aluminum can carry significantly less watts than copper of the same size

this is kind of ok if you plan and size for that (and treat it right), but disastrous otherwise

there are heavy guage battery cables that are faked with aluminium. scary stuff when it's carrying 200 amps

@kravietz Sorry, no, I don't believe half of UK homes are wired with alu. I've never come across it and I'm pretty sure I'd have heard if it was at all common. There might be a few older houses with it but if there are any it's quite rare.

Things which are weird and questionable in UK house wiring: a) ring final circuits and b) older lighting circuits without a protective earth.


@s0 @sandzwerg
Also: if you use speaker cable, that looks thick, be aware a lot is also made of aluminum the same way.

@s0 I had that problem with a Harbor Freight trailer. One of the lights stopped working. Went to repair it, and the wiring was missing from the insulation! Turns out the cable had turned to powder inside. Very dangerous indeed.

Good way to start a house fire.

@s0 Oh no, I though CCA was only used in cheap network cables! I didn't trust them with PoE let alone mains!
@s0 Oh, in saying that I think my cheap eBay jumper cables are CCA, but seem they work ok ¯\_(ツ)_/¯

@parus at least with jumper cables, you’re not exactly leaving them unattended to catch on fire.

@s0 I once had a knockoff cable where the ground wasn't connected? Like Schuko plug, three conductor cable etc. but within the Schuko plug the inner metal thingie and ground contact in the hole was missing‽

@s0 Like you had the damn ground wire, and IIRC also connected on the other side, but why save on that tiny bit???

@s0 After having one too many fires I've started opening all power supplies I get to check them before I plug them in, and toss all the cables in the bin.

Most power supplies also go in the bin - my favorite was one that had a bunch of wires inside cut on both the DC low voltage side and the mains side, dangling around with exposed copper. Shaking it would put mains voltage on the DC plug.

@ChlorideCull loving all the yikes stories here.
So many power supplies that have IEC connectors but just don't connect the Earth pin through to anything -- which is against regulations here and they cannot pass T&T. Had to toss one such supply at workplace#2 recently.

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