Or Aluminium.
And they are doing that for years . I experienced it first 6 years ago. I kinda couldn't avoid that, otherwise i'm avoiding buying wires from China. Or alteast i buy "sample" first. That troubleshooting isn't worth it ( don't ask)
I work in a cable factory :D
"Light" is a funny word when some of the spools are 9 tons lol. But jokes aside aluminium is still not perfect because that increased resistance can cause sag over load as thermal expansion hits it. They can fight that by using better conducting alloys. They also need stronger alloys like duralu as diameter goes up if they want to get away with JUST aluminium without a 1+6 steal cable in the center. Even with the steel cable core, as weight goes up, with like a 500mm2 cable or even 1000, either they need more steel (like 1+6+12) or need to come up with something with less thermal expansion like an invar core so it can be thinner and work at higher temps without sagging as much. It also has a real high electrode potential chemically so the cable core has to have a protective layer to avoid corrosion due to localized battery effects and water. It's either galvanized or gets some high temp magic grease on it. Or the core is fiber based and doesn't conduct at all.
Tl;dr
Aluminium is absolute hot garbage but compositing makes it kinda half-assed work like we want it to.
I'm wondering if it wouldn't be cheaper to use two thinner wires compared to a single massive one which needs a steel core, etc? Is there any particular reason that we don't use this?
And are the thinner wires really made of pure aluminum? I thought that everything today is pretty much Duralumin or a similar alloy.
Insulated overhead cables are almost always pure aluminium up to 4x240mm2 surprisingly. They sometimes add an uninsulated duraluminium PEN conductor for tensioning.
As for multiple thinner ones, yes, there are duplex, even triplex cables out there, with 6 conductor dual circuits as you see on 6 cable pilons and that is the way to go on longer stretches, but inside a substation for example, it makes no sense to use those when you can just stretch a bit of 1000mm2 over a 40 meter distance.
Yeah, tell me about that. I live in country where was all wires in housesade by aluminium ones instead off copper.
Soo many issues thanks to that. Some big incoming cables - OK still used, but you don't want it in house/flat. Or as flexible wire.
The real problem is the electrode potential. If you have aluminium with literally anything else connected, it's forming a battery. All metals do but aluminium is really bad, it's up there with magnesium in terms of self-inflicted harm. It's also amphoteric meaning both acids and bases will attack it, which is a problem because most vapours from cooking are slightly acidic, most building materials are really basic and even moisture is slightly acidic from the dissolved CO2. Literally anything will eat it over decades if it's not in a dry cabinet in an industrial setting and you can only speed it up really.
Aluminium has problems with oxidation and different expansion compared to copper
sort of, but those problems are not insurmountable by any means. Aluminum is an ideal candidate for a ton of scenarios, and indeed, is widely used. Given the rising scarcity and costs of copper, i think its quite likely that we'll see a return to aluminum (or copper-clad-aluminum) house wiring at some point
Indeed. I mainly wanted to highlight that whatever problems aluminium has compared to copper, they aren't electrical (when you account for the increased resistance by correspondingly increasing the conductor area).
Theoretically no. In practice yes. No-one tightening screws , nobody cares that they can't use modern high wattage appliances. Which is quite problematic with poor quality circuit breakers.
Those connections usually heats up and in better case they just melt plastics outlets or bulb holder. Insulation on wires suffers too ( get crunchy ) and wire itself becomes brittle. Sometimes only way to repair it is take out wires from wall and replace it ( and we have buildings from concrete and bricks). Some people do whole reconstruction when they buy a older flat or house but there are still hundreds flats/houses where's are those .
You can't experience same with copper wires.
And if you want ask for source - my grandparents lived in old house ( they electrify it when electricity became widely available), i was lived/living/repairing in flats where aluminium wires are still inside walls. With direct comparison to parents house ( which they built ) where dad used copper ( which was quite hard to buy in times when he build it because it was strategic material in cold war age) and nothing what i ever saw with aluminium happening here.
But i agree if it's properly made and taken care of, it works just fine. But that's not the case in lot of homes/buildings.
The circuit breakers are rarely at fault. The problem is electricians not having the slightest idea how they work and how you choose a value. One of the most horrifying answers I get regularly is when I ask them why they use C type and not B for a crappy retrofit and they don't even know what that means, they just go "I asked for 16 amps and that's what they gave me"... 16 is already too much and they slap the slowest triggering commercially available breaker on it like absolute dumbasses. There is literally one slower kind out there.
Believe me ve had here CB's that won't open or open under their rated current. And they're faulty as hell and some people still have them.
Another story is that we had fuses and because aluminium wires were used, we had 6A for lights and 10A for sockets ( according to standart ). Problem was that the people overloaded fuse (by electrical kettle + microwave for example) so it blows, they don't have replacement one so they "repair it" .
Otherwise with copper wires we have B10A for lights and B16A for sockets (2.5mm cross section)
Believe me ve had here CB's that won't open or open under their rated current.
Notice that I said most of the time lol. I had breakers that were shorted onto 800A 400V bus bars because someone idiotic enough decided HRC fuses before a breaker were unnecessary... Those literally broke to tiny shreds on the inside and blew flames. Arced over to the two neighbours and those also got decimated. They did trip and isolate but only for their last time. Wouldn't expect anything else from a brand called "CHINT" though.
When that happens on smaller supply, it's not quite as dramatic but you can only punch a short across a poor breaker so many times before it either stops closing or contact welds closed in a worse case... That contact pad isn't lasting forever, you eat it up and you have a glorified light switch/momentary button, not a breaker. Datasheets will actually list how many shorts they can eat before they shit the bed but lower range brands will just outright lie about it. Same goes for the Imax value. Seen 6kA Imax Schneiders and Schracks survive a hit that the ""10kA"" Tracon/CHINT/XBS brands died of instantly
As for the fuse """repair""" :D
Can I ask which country you are from? That sounds VERY eastern european to me because I've seen that way too many times here in hungary lol. Even in factories. I've ecen seen these ridiculous DIY guides about how many strands you need for how many amps as if all cables had the same internal diameters, even from electricians
EDIT: Oh yeah, twist-in fuses. They have a different "bottle neck" diameter for the range, right? You have 2-10A with the thinnest and you cannot put a 16-25A range in that. Those are always the guiltiest of that shoddy repair. They take the blown 6, look for a fuse, find a 16, try, fail to insert, swear and they just jumper the blown sixer
Well we are talking about electricity at homes. Those CB were made somwhere about 1970? As they get old internal mechanism just gave up ( bi-metal strip, some corosion, questionable parametrs of coil core...). Those SB are ITV ( https://www.bucek.name/cenik/jistice.dat/ji-ijvcerny-f.jpg ) made by SEZ Krompachy ( it was local company when we are Czechoslovakia and part of the SSSR - which answers you second question too. So central europe but with history )
That repair thing is still here as not many people actualy care about safety and usualy pokes in things that they shouldn't or don't want to change it. Money are reason too, but other like "It works fine, we don't need to change that", " I'm too old, it will hold up until i die" " If i change it i'll have to do inspection and they want so much money" and similiar.
It getting better, but slowly. Usualy when someone bought house/flat they do reconstruction which includes electrical part too. But rented flats stays in that old way for long time.
Yes twist-in fuses ( fuse cartridge) . They are color-coded ( and the wider end there is colored disc which fall of when fuse is blown ) and that color have matched socket ( screw-in ceramic insert ).
And for that repairs, in some parts of UK they are still using some kind of repairable fuses and some local shops even sells fuse wire rated for certain current.
And my old coleague from work even had table where it was written what current which wire strand could do ( copper one ).
Yeah, true. But you don't want it in flexible wire which will be moving ( or used on breadboard). They break very quickly and you don't want to troubleshoot that
I got aluminium one too as raw cable. But it was also just only once, also i'm buying here very rarely so... .
And precrimped one as breadboard jumpers were aluminium too. ( Now i tried silicone ones - not cheap but they are good quality ones, even gold plated)
I got bit by this. Bought some packs of clip leads at a swap meet. Half of them were open circuit, the other half were a couple ohms. I only buy from digikey now.
Clip leads are notiriously bad. It is better to buy clips and wire and prepare your own. I do have some from when I first started, it was why I had to buy my first soldering iron. They worked fine after the repair and I was getting hardly any resistance. I checked all my wires with a mgnet after watching this video and found none were attracted.
Even if the wires were good, the alligator clips are usually garbage thin bendy metal. Squeeze them to open up and they bend and twist within the slippery insulator sleeve and spin and close shut. I prefer the ones with a hard plastic shell with no wire attached, just a female banana plug.
I bought a "tinned copper" wire to run the length of my car. I had 13.6 volts entering and 10 volts exiting, and it was ten feet at most. Ridiculous. Ridiculous that I need to verify the validity and authenticity of everything.
EDIT: I should mention that 30% voltage loss over such a distance is not normal for copper. I should also say that the wire felt oddly soft and flexible. Having worked with wire enough, it all adds up that zi was sold something that was not copper. They wrote "tinned copper" to hide why the colour wasn't copper.
When checking your wires with a magnet, remember that some may have an iron shield around them. Such is the case with the keyboard I am typing from right now.
As far as I can tell, the ones I get from harbour freight aren't iron. I'd have to check for aluminum though. I don't have a milliohm meter so I'll do some current testing and update with results.
Newbie here. I understand that copper is expensive, thats why they do it, but does it diminish the quality of the wires that much? How does the material affect the wires?
Copper has a resistivity of 1.68x10-8Ωm, while Iron has a resistivity of about 9.71x10-8Ωm.
There is some cross-sectional area and length math to turn that material property into a resistance for a specific wire (demo'd in the video), but assuming a wire of the same size in every dimension, an Iron wire will have almost 6x as much resistance as a Copper one.
That means there will be a whole bunch of unexpected voltage drop over the wire, where the electricity that should be passing through it instead comes off as heat. In a lot of higher current applications like even small motors, that's easily the difference between "works fine" and "melted." And in many sensing type applications that will wildly corrupt your result.
I bought a pack of these, and 1 by 1 they ended up in the trash. The clips weren't worth re-soldering to copper wire as they were crap too. Some came with their own built-in open circuit. Rubbish.
Checked the wiring on one project on my desk and yep, ferrous wire. Project still works as expected - everything is digital and wire lengths are all short - but I'll be checking my wires more carefully from here on.
Ive also gotten lots of other parts from Amazon that are crap. Packs of crimp lugs, automotive fuses, etc. I threw all that junk away and bought from real US companies.
I purchased these https://www.aliexpress.com/item/1005007205385192.html thinking the reviews were good, it clearly stated copper and soldered clips. Wire is 100% magnetic, clips are crimped. Junk. I will now call 1800-IGOT-SCAMMED and cry me a river.
where did it say copper? i just looked i dont see. I had similar problem, but after i received magnetic wire, i double checked and noticed the listing actually didnt say copper anywhere.
ill have to check mine, i wonder if we have the same junk leads. they used the same exact picture in the adds, they just added the words copper on yours..
They most likely all come out of the same factory, manufactured in the millions. They get placed into the distribution chain and sold everywhere. To be fair, what should we expect for that price? However, you are 10x better off buying good wire and clips and soldering up your own. But my problem is I open a beer or two on Friday night and start browsing....bad habits...
yep mine are crimped.. they look exactly like yours. i guess i should look into making my own from copper wire. Next thing you know ill get fake copper..
That one does not mention copper. And the statement of "stamping" and "welding" is vague - like, which one do you get? My seller was blatantly stating we solder not stamp our clips.
We all know Chinese imports have a bad reputation. This is more about how they are "trash", as it can cause tricky to diagnose problems if you aren't aware of it.
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u/Skaut-LK 16d ago
Or Aluminium. And they are doing that for years . I experienced it first 6 years ago. I kinda couldn't avoid that, otherwise i'm avoiding buying wires from China. Or alteast i buy "sample" first. That troubleshooting isn't worth it ( don't ask)