How WAGO terminal blocks are arranged

Thanks to the author for the second part of the material on the WAGO terminal blocks ..

But, the question from the first part of the article smoothly swims into the second ..

As far as I know, the resistance of ANY contact will be higher than the resistance of a solid conductor, so in order to compensate for this difference, it is necessary to increase the AREA of the contact spot to a value greater than the cross section of the wire itself, this occurs for example when twisting, tightening under the screw, etc. ,

In WAGO terminal blocks, the area of ​​the contact spot (in the picture, that part of the wire that is just pressed by the spring) is smaller than the cross-section of the wire, it is even visible that the remaining tail part of the multi-wire core is “fluffed” which naturally does not “benefit” the reduction of the terminal resistance of the terminal block.

Of course, I heard that these terminal blocks are used on fairly important projects, and are certified, but no one can explain why this is so ?!))

Typically, the contact area is increased not in order to somehow strongly affect the transition contact resistance, but to increase the heat sink from the junction of the two wires.

Of course, solder twisting or welding will be more reliable. But these methods of connecting wires are laborious, they pipe additional equipment. Then, this must still be able to be done qualitatively, by technology. And then no special skills are required. I cleaned the wire, inserted it and the connection is ready. With large volumes and copper wires, the best is WAGO terminal blocks, after all - the world leader in the production of terminal blocks. I climbed through bourgeois sites via Google Ghrome (it automatically translates), so WAGO is recommended and used everywhere. Everywhere it says: "high reliability" and "German quality." I don’t know, I like these terminal blocks, and indeed “new technologies”, but I always look with interest at progressive things. Interseno would, of course, hear the opinions of people who regularly work with WAGO terminal blocks.

I myself like new technologies))), if they do not go against the laws of physics and logic)))

Again, not for the sake of argument, but for the sake of the true))))

As a designer, I’m afraid to order such things for objects.

Although WAGO managers came and brought a bunch of catalogs, and told how everything is reliable and everything is cool, but they did not answer my question ....

andy78,
You yourself mentioned the heat sink from the point of contact, the excess heat just appears because of the high transition resistance ....

Electrical contacting is a very complex phenomenon and it is not so simple as it immediately seems, and here simple logic can fail. Transient contact resistance depends on many factors: the material of the contacts, the state of the contact surfaces, the strength of the contact pressure, the ambient temperature. Touch area is just one of the factors. Yes, a multi-point contact allows current to flow through several contact junctions connected in parallel, and the contact transition resistance is reduced compared to a single-point contact. Therefore, surface contact is better than point contact.

But, in the "theory of electrical apparatuses" there is such a formula: Rper = e / (P to the power of n). P is the compressive force of the contacts, e is dependent on the material and shape of the contact, n is an exponent that characterizes the number of points of contact.So, this indicator has a maximum value of 1 (with surface contact). Moreover, as soon as we left the point or linear contact and received at least 3 points of contact, it is already superficial. It can be seen from this that an infinite increase in the contact area is not practical, since n does not exceed unity, and from this we can conclude that the transition contact resistance depends very little on the contact area.

Contact surfaces increase with increasing current, not in order to reduce the transient contact resistance, but simply that with increasing current, losses increase and their scattering requires a large surface. I think that the WAGO designers took all this into account, tested it and made their terminal blocks just like that precisely because the touch area in this case is not the most important thing.

I agree that the transition R depends on many factors, but for example we connect two conductors with a cross section of 4 mm2, and if the contact area is less than 4 mm2, then it does not depend on other factors (pressure force, temperature, humidity, etc., even if the transition platform is soldered with silver alloy), we will get a section of the circuit with a cross section below 4 mm2, and when all the load on which this wire has been calculated, the contact will start to warm up (naturally, if the cable section during design was not exaggerated every 5 times relative to the load))) )

Regarding heat dissipation at the point of contact ..., I also disagree, consider any screw connection, for example, in a socket, switch, no additional. There are no surfaces for heat dissipation.

The transition contact resistance will be even with the same conductor cross section and the area of ​​the contact area, it appears at the point of contact due to microprotrusions (current never flows over the entire cross section of the wire, but only through separate areas). The main task when creating contacts is to make sure that the contact resistance does not increase during the operation of the contact. This is achieved by two things - sweeping and creating a contact click.

What I described above is the theory of electrical apparatuses, the formula was obtained experimentally, you can see the proofs in any good textbook on apparatuses (Bul, Rodstein, etc.). I taught this subject for 8 years.

And in outlets, all screw connections are sized in such a way as to sufficiently dissipate heat. There, for this, no additional surfaces are needed.

But who argues)) that the transition resistance WILL! even if the conductor cross-section is equal to the contact surface area,

Moreover, this resistance will be GREATER than the resistance of the solid conductor, (even if we weld or solder two conductors of the resistance of the section with welding or soldering, it will be more than the resistance of the solid conductor)

I said this in one of the first posts ...

That is why, even with PERFECT !! parameters of humidity, temperature, and pressure, .. to reduce the contact transition resistance, (or at least equal the resistance value of a homogeneous conductor), increase the area of ​​the contact spot so that it is NOT LESS THAN the area of ​​the conductors.

No offense...

the fact that you taught a subject for 8 years is not an indicator, for your 8 years of study you have seen enough of all kinds of teachers, and only 5-10 percent of them were adequate people who rummage in their subject, and who justify everything without problems they say ...

The rest is retirement debris (with all due respect to the elderly), but it’s a crime to train a new generation of specialists with inadequate retirees (for example, recently, from a friend I hired a student who believed that a transformer was needed to convert AC voltage to DC .. ., and now he is already considered a socialist))))

I hope that you relate precisely to these 5-10% of adequate teachers who understand in their subject)), because talking with dolbaks from the remaining 90-95% is useless ...

I don’t know where you studied, but in my life I have come across mainly “adequate teachers”, but “adequate students” who are trying to understand something and generally want to study nowadays 5-10%. Even if someone is not very lucky with the teachers, but the person wants to, he will always find the information he needs and will understand the essence of the issue (for example, on the same site bgv.electricianexp.com). The problem is that now, for the most part, no one wants anything. If earlier in the group 2-3 people did not study, now they are studying the same amount, and the rest suffer and suffer. Do you know how interesting it is to work with such sufferers? So you have to somehow self-actualize on the site.

I agree that there are less and less adequate students every year ... (this is the policy of our country, but this is a political topic that has nothing to do with this site).

I studied at the technical school and at the institute, and so you won’t believe in the technical school, the percentage of adequate teachers is higher than at the institute))).

At the institute, many (almost EVERYTHING) teachers stupidly lectured on paper, and then on the standings you should write TUPO word for word what he dictated, well, so who copied from the notes ONE TO ONE was an excellent student who tried to say something In my own words, I received an estimate between 2 and 3))) (and I did not like to write off)))), i.e. these are teachers who over the years have learned their notes by heart, and do not perceive anything else ...

If you are hinting that I am self-fulfilling here))) there is nothing to do from it, then this is not so.

In fact, I'm trying to dot the i, in some issues, primarily for myself, and not in order to annoy someone)).

As for the topic of transition resistance, I would also like to listen to the opinions of other visitors to this site, so to speak, to judge us))

Yes, everything is fine. I like your comments. What kind of grievances can there be? You have your own position, your own view of things. It's good. When I wrote about self-realization, I meant it myself. It just so turns out that the work of the teacher does not bring full satisfaction, and work on the site allows you not to stop in place, to constantly develop.

I look forward to comments from other visitors to the site regarding the issues raised here (WAGO terminal blocks, their device, the effect of the design with a flat spring clip on the transition contact resistance and, in general, on the reliability of the terminal blocks).

I agree with the posts knotik. And I add, in the production of any terminal blocks there will be a deviation of the parameters (and sometimes a hidden defect). This is no longer a simple, but a more complex system, with pressing, installation accuracy, etc. Therefore, the terminal blocks should have a large margin of safety.

I personally don’t understand why to fence the garden, it’s easier and cheaper to cook, you can solder it for an amateur, if a couple of boxes or if there is a crucible ....

By the way, these terminal blocks are super expensive, so I don’t know who uses them))))

))))))))))))))))))))

The perfect lure for suckers and hoses !!! Better tell me who paid for the advertisement? He made HUNDREDs of objects (both large and small). There was not a single complaint! But it never occurred to me to make internal wiring from a multicore. Moreover, think of the connections on the terminal blocks! If the author of the advertisement (above) went to school, and did not collect bull-calves by the porches, he probably would know what POINT CONTACT is !!! Try (for laughter) to load the terminal strip with a rated (passport) load. Measure the temperature. Few? Repeat the experiment after a couple of months, when the constantly hot conductor is oxidized. Well, if the client by that time does not burn ...And I don’t give a grudge to teachers of technical schools and institutes - it happened to me to see other people's burned objects! These teachers would be there !!! God had mercy, in the Serpukhov Instrument-making industry there were none!

I AGREE YURI !!!!!

There is GOST 7399-97 where it says the use of wires and cords, so that about a strand and should not be discussed in stationary wiring ...........

Almost all modern sockets and switches of well-known manufacturers (the same Legrand, ABB) come with flat spring clamps. Perhaps they are all idiots there? Or is it the targeted sabotage of the bourgeois? They simply underestimated us. They put us their rotten terminal blocks, but we are all ideologically savvy and are not going to live by world laws. What for us their technical progress? We have a hundred years, everyone lives on twists and at least as much will live!

I have been installing air conditioners for 4 years. During this time there were more than 300 objects. I usually connect to the nearest junction box. For all the time I have never seen a welded or soldered twist. Everywhere there are ordinary twists and often even non-insulated ones, and there are also connections on ordinary plastic terminal blocks with screws. When I connected the air conditioner, I put the vagi on and not once in 4 years did anyone show anything. I think that it’s just profitable for electricians to criticize the new terminal blocks, because if they weren’t there, they would have more work, and without electrical knowledge, I normally connect everything with the help of vag and no one complains. Therefore, all the horror stories written here about vagi are all complete unprovable nonsense.

Yuri, and why so much aggression? Is it a hard day or a character like that? (This is about the bulls in the hallways, suckers and hoses). Or are you all who do not share your position - subhuman?

This is not an advertising article, but an informational and educational one. If there was an advertisement, and someone would pay for it, then at the end would be the address of the site or store where you can buy terminal blocks Wago. Don't want to pay for the anti-WAGO article? I see that the topic of terminal blocks is clearly not indifferent to you.

Then, where did you see the point contact in the terminal strip? Contact flat. Maybe we will argue what is point contact, and what is planar? And you praised your college so much. Seen in vain praised. Read the tutorials.

And you didn’t do those burned objects that you scare everyone here? And what, the result of the investigation was: "The cause of the fire was the terminal block Wago". Something I strongly doubt it.

In general, the next time you rub somewhere else, otherwise you are completely rudeness and no constructive.

Andrew, But did you put those sockets with a spring contact, for example ABB?

There is such an interesting document, especially for you:
DBN D.2.3-8-99
Table 1 - the norms of waste material resources
15 Wiring accessories (switches, sockets, cartridges, etc.) - 2%

So, of the two hundred such ABB outlets, not the cheapest, the contact point was bad, crooked, did not hold, etc. a dozen for sure .... Even worse than the norm of the document)))

A twisted or soldered twist can live a hundred years, we'll see.

Marat Sharash-installation))

And you are proud of this, that without understanding what you are doing, you climb to where you should not?

And if it is not clear to you who did what, then this does not mean that this is normal.

Sergey, what kind of statistics is this, and who led it? Do not slander ABB - a more than serious company and certainly does not knit brooms.

Do electricians here only deal with their electricity? They also climb where they should not climb. Let's be honest - now everyone is trying to do everything on their own, which does not necessarily mean poor quality of the results. And when there are things on sale (such as vago clamps) that help to do their job normally without dancing with a tambourine, then they should be used. For the interest of one of my friends, I asked him who had been scolding with these clamps for ten years already (I always take this from him). He had no complaints about vago. Never been! Why then to the car so much negativity from electricians? He was even very surprised when I tried to describe the flaws invented by seasoned electricians. The Germans will not do anything anyway!

Sasha ABB is different, even the most run-of-the-mill, different models and workmanship.

I didn’t set Legrand, it is a higher class, and I think there will already be corresponding quality for that money.

Regarding bad contacts, these are my personal impressions after installing a large number of those outlets on one object, i.e. my statistics.

In ABB with simple screw clamps, (they were cheaper), the marriage is much less, fit into the norm)))

And in the document is the normalization at the state level.

Marat, I personally have a negative attitude, and I see a logical explanation for this.

Germans and Germans, rather Chinese))) But the development is yes, I agree.

And besides electricians, I’m still involved in a number of areas, but for this I’m studying the necessary information ....

to Marat,
as I understand it, you feed the condo with a cable of at least 2.5 sq. mm. and use the terminal blocks on the same section.
ran over the power of air conditioners, operating current of the order of 3-5A
Section 2.5kv.mm. holds current about 25A + -
it turns out that the cable cross-section is selected with a margin of 500%, and accordingly, a current of not 25A but only 5A flows through the WAGO terminal block, it is natural that these terminal blocks will not fly out with such a current reserve.

knotik)))) Well, yes, 500% is a joke))) I didn’t think about this side of the question))) with this load, they can work as you like and just twist.

I use wagons when installing electric stoves (5 years), and so far there are no problems, they keep 3 phases on an electric stove at a maximum load of 12 kW and they are used every day in restaurants. And I did not see any heating of the overheating of the combustion of the burnout of oxidation at the site of the terminal blocks. When replacing the plates, the terminal blocks were like new. So for me, these terminal blocks have fully justified themselves. And I began to put them on the advice of a friend, he worked at many racks in Europe and said that there are only these or similar types of terminal blocks from other manufacturers that they put there - he never saw any twisting or soldering. And according to your statistics and contacts, 10% of European houses should have already burned down or wiring failed)))

electric stove, this is a serious argument))
question toIgor,
What was the wago cable and terminal strip cross section used ??
and wago with a spring clip? or screw ??

knotik, now I mainly use the 222 series, the same as in the figure above. The cable diameter of 2.5 mm2 is the one that comes from the meter (but again, 3 phases are used, the maximum current in the plates is usually 16 A per phase, some plates can be thrown into one phase but 7.4 kW, for example, an inductive plate - this is 32A, which in most cases makes it difficult to connect such a plate), in the plates it is mainly 4 mm2, but they are stranded, which, according to the instructions, is permissible for VAGO. If the plate is connected only for one phase, then we no longer use such terminal blocks - sometimes we use welding but basically we put special sockets. By the way, a couple of times I bought poor quality terminal blocks.I think the Chinese fake, since the color and quality of the plastic was clearly different from what you usually had to work with, in general, I threw them away from sin. Right now I order from Europe, although delivery takes time, but the quality is excellent.

Igor,
Thanks for the detailed answer .., as I understand it, in the terminal blocks of WAGO theory and practice are contrary.
In PRACTICE everything seems to work, even for powerful consumers !!, although THEORETICALLY it is not clear how .... ((
although 16A on a 2.5mm2 cross section is also rather weak, at least load 20A)))
in the meantime, practice is not confirmed by theory ... it's scary to use them))

I don’t know what about soldering, etc. no matter how much you climbed into switchboards and boxes, it’s just awful that snot and twisting are going on, it’s better to let them in the car than in such a state as it is, as for bolted and threaded connections, there needs a constant pull, even those sockets, switches, RCDs and automatic machines ALL need a constant stretch!
While in work I always use terminal blocks for 5 years, everything seems to be clean! =) He studied at the Taganrozh Radio Engineering right now, sort of like TTI SFU, if someone does not know one of the strongest in the world ...

Why not conduct an experiment: load the terminal block to full or almost full, then see what happens to it after a while. Of course, experience should be protected by automatic machines etc. And everyone will be able to draw some conclusions.

Vagi are only good for hanging lamps, the wagon from the kettle correctly connected at the dacha flowed, although there was still a double power reserve, from the declared one on the wagon itself, I saw leaked wagons in boxes, the insulation housing first fails, then the contact disappears.

Sergey, don’t be dumb. I understand that there are people who are ready to prove with foam at the mouth that under the communists the salary was higher, there were fewer queues and life was more free. But whatever one may say theory is theory, but practice shows that vagi is a fairly reliable way of connecting conductors. If someone wants to stand with a soldering iron or a welder - no one forbids. Let them stand. Only damn the Chota Germans live an order of magnitude better than us, earn better than us, and in the world their quality is respected, which can not be said about us. If you still have aversion to everything Western that has been grafted on since childhood, then you will have the flag in your hands and a drum around your neck.

In my practice, I met twice that spring terminal blocks burned out. When I do the installation I prefer welding or soldering - not a single burnout in 10 years of practice.

The contact resistance of the contacts is determined by the pressure force and the number of contact points. If there is no loss or welding, all contacts are point. Of course, welding and soldering is a good, but very laborious technology. In addition, if done sloppy, both of them fly apart over time. That is the whole problem. Spring contacts are designed "for a fool." They provide pressure in the contacts "forever" - and therefore clean. And the contact resistance over the area is not calculated. The resistance of the conductor is determined by its LENGTH. And the contact has no length, so to speak. So spring contacts are a good thing, as I say a physicist, I worked a lot with different powers and frequencies.

We are private electricians, engaged in the maintenance of various facilities, conduct electrical work, and also perform small work in private apartments. In our work we use terminal blocks VAGO 773 series. They are very convenient in operation (especially if it is necessary to connect aluminum and copper conductors), installation is greatly simplified and time is saved.About the reliability of these devices, I can give an example from personal practice: on one of our serviced objects, VAGO terminal blocks were installed in the lighting circuit in the junction box, the lighting lasts 12 hours daily (car service), the current consumption is 15A (measured by clamps), respectively, this current passes through these terminal blocks. They have been standing for half a year now, we periodically check the heating of these terminal blocks - there is no heating at all!

Hello!

I read many of your comments, so I propose to stop arguing and cursing, but simply refer to the official catalogs of terminal block manufacturers. In addition to WAGO, see Phoenix Contact data. There you will find the attached test results, areas of successful application, etc., in a word - a lot of useful information for the general electrical development. And you won’t have to argue! At least in terms of contact area!

Personally, I'm for the terminal blocks! Moreover, WAGO for construction tasks are very inexpensive.

Good luck!

By the way, what can you say about the cut-in contacts when the conductor is connected with a rotary sharp blade of the terminal contact? There the area is very limited.

See Phoenix Contact.

I have been using wago clamps for 7 years. Not a single complaint has been received.

And how did the carriage behave with KZ did someone check? I saw the burned vagi several times, although the cause is unknown, perhaps the curvature of electricians.

Now there are a lot of Chinese WAGO! You have to be careful! So they are burning .... People take what is cheaper from us, and then they shout WAGO has melted!

Of course, all the electricians gathered here are very experienced people, but it seems to me that they are not entirely attentive. Have any of you noticed that the permissible current load for a conductor is 2.5 sq mm 24 A and for 4 sq mm 32 A, while according to the table for choosing the cross section of the conductor, depending on the current strength and voltage, it allows 30 A for 2, 5 sq mm and 41 A for 4 sq mm, respectively. The difference is very significant, and seems to me dictated by engineers for safety reasons on the contact area.

p.s. Marat, your comment really amused me: “I think it’s just profitable for electricians to criticize new terminal blocks, since if they weren’t there, they would have more work, and without any special knowledge, electricians normally use everything with the help of vag and no one complains. "

What kind of "special knowledge about electrician" is necessary for twisting? This can be taught to anyone with a head on their shoulders in half an hour. And from the knowledge when connecting the power to the air conditioner ... well, you do not confuse the conductors with honey by themselves, right?

As for the reliability of the contact through Vago, I can confidently say that I myself am an electrician, and when I first started using Vago in junction boxes, we tested them in practice, gave the load and YOU STARTED TO MELT only after 6KW load was applied to them and then the wire was used together with the wire VVG ng 2 , 5 mm, so I can say a reliable connector, the electricians will understand if the entire wire melted the whole cable, it doesn’t matter whether the switch box has already passed or not =)) So the test in practice confirmed the reliability of Vago.

For wagons, there was a great way to test on 12v. There you understand the currents. Oh halogen. The vagi died and the stench stood for a long time. Heating quickly leads to a change in the characteristics of the contact, and if you take into account what is now everything. Strange alloys. So they and oxidation heating do their job. Vago work yes, but there is a limit to everything for large currents, a greater heat dissipation is needed. Thermal conductivity is the slow diffusion of additional vibrational energy. And how do multicomponent alloys behave in the same one god ... I don’t think that the bourgeois will be littering with money and they are not fools.They know how much work and materials cost. This is our penny job and we can twist and cook and solder. And on metals, God himself commanded. Where can. We have the whole country on snot but where we need it we twist or solder or cook. Turn on the brain, otherwise any connection will not help.

people! what are you doing you pursue speed and expediency, neglecting safety! we electricians always have to do everything very reliably, and these calculations and disputes are not needed for those people (albeit UNITS) those who have suffered from such dubious innovations. I do not argue that innovation is needed, but not so ... be prudent and do not wish people harm)

Wago is really rubbish. only for low-power light. A terminal block with a stub has built up a terminal block. turned on the washer, after 15 minutes, the terminal was already to the touch like chewing gum. I did not begin to experiment further, I connected according to the norms of wiring (without a vagina).

Self-clamping, screwless, spring-loaded, WAGO, Weidmuller, Legrand, ABB, Hager, OBO and other manufacturers terminals in junction boxes are used only by unknowing people or deliberate hack workers, since it’s faster, more convenient!

Self-locking, screwless, flat spring, terminals worse than ordinary twisting !!!

Tell me please ! How to cook multicore copper in the distribution boxes? If it is not difficult to describe everything in order, in detail. Thanks in advance for your reply !!!

From personal experience I will say that these terminal blocks are of very good quality, unless of course the load limits through them are exceeded. I saw it myself through one line on these terminals. They missed the 3rd load norm and even less than the norm passed through another separate line, and of course the power line burned and melted, and the second separate one worked without problems for a year. The conclusion is that their maximum parameters should not be exceeded and you will be happy.

Vago is for different purposes. Look at the catalog on their site.

WAGO terminal blocks belong to PPE, which are allowed by clause 2.1.21. But if this is not enough, then all WAGO terminal blocks comply with GOST 10434-82, GOST R 51323.1-99, GOST R 51323.2-99. If paranoia still does not let go, then we ask in the store for a certificate of conformity for the purchased devices (absolutely everything).

I also hobble electrician. I decided to share my experience with VAGs. Often called to private traders to replace the WAGI in soldering with soldering. I noticed that often defects with VAGs are associated with a poor-quality compound. That is, the electrician plugged the wire into the VAGU poorly, it is not clamped inside but simply touches the contact. And the reason, in my opinion, a monolithic wire is difficult to check in a small wiring, flexible is easier to check. Therefore, probably the box should be big.

It is interesting to know: - how long has the VAGI been used? A familiar grandmother has been holding aluminum twist for 50 years. Can WAGO so or should we wait? Every electrician understands that the wiring is replaced once and the client wants to make the wiring "to death." Maybe, really, soldering, welding, but VAGI are also allowed by the PUE p. 2.2.21, as the namesake wrote. So the electrician is protected anyway? And the client? !!

Andrew, when using Wago terminals there are several nuances. Firstly, this is the quality of the terminal blocks. If this is a fake, then you can’t talk about any reliability, poor-quality connectors will make themselves felt very quickly. Secondly, the wiring must have reliable and correctly selected protection against overcurrents. Wago terminals can withstand the declared rated current, but they can be damaged quickly when overloaded.If the protective devices are selected correctly, then, respectively, the terminal blocks will last a long time.

In practice, it often happens that after installing the wiring, some changes can be made that reduce the reliability of the wiring. For example, the circuit breaker is replaced with a larger rating, not taking into account the features of the installed wiring. As a result, all Wago burn out in junction boxes due to overload.

Therefore, I believe that the reliability of Wago can only be guaranteed if the wiring is serviced and operated correctly. In modern realities, for reliability and protection "from the fool," it is better to connect the conductors by soldering, welding or crimping. But this is better for the client, but not for the electrician. For an electrician performing orders, Wago's advantages are not only convenience and speed of installation, but most importantly - a greater number of orders in case of improper further operation and maintenance of the installed wiring.

I had the patience to read all the posts, uh ...

First, let's take a look at the second picture from above. The stranded conductor is inserted into the spring contact. And not a single hair was left at the beginning of the hole ?! Why is stranded advertised? Because with this image size, the mono-core would touch at two points, above and below. That there is no buzz for advertising. If the conductor is crimped with a needle-type tip, then "the same eggs, only side view" + additional work and tips.

Secondly, no one thinks about the quality of those terminal blocks that come to Europe and the CIS. There is the slightest marriage and at least the whole batch will be rejected, and then they will have to pay fines. Or maybe they’ll be deprived of the license to manufacture such products. And we have? A "businessman" comes to China and says I need such things that cost $ 10.00 in bulk 1 million at a price of $ 00.10 and the Chinese agree. And then this shit spreads throughout our territory. And no one will check. It looks like, but the materials in the manufacture are not at all the same!

Thirdly, the quality of the copper core is not at all those that are used in Europe. Copper should be electrotechnical which is produced by electrolysis from a melt of 70% copper. Therefore, a soft copper core with a small warming crashes into contact and thereby increases the conductivity, probably the Germans thought so. But the steel, copper-horseradish knows what kind of vein she is not capable of. In our Khrushchev’s still there are aluminum wires which are WELDED in the boxes. I cook everything in work, and even if there are 2 or more outlets in the block, then one socket will be put deep and there will be welding with a tap for two. And installation is convenient to do and convenient to maintain. The size of the boxes using vag needs to be increased, since the twist with welding takes up less space, which affects the customer’s budget. Yes, and the vagi themselves cost money. And for installation with or without wagons, the price of work does not change. But the most important thing is that with a high-quality 500% connection, the electrician sleeps quietly, even if the rams increased the protection rating.

Then someone wrote about a school physics course from which he learned that current flows along the surface of a conductor. My school physics course did not tell me anything about this. But later I learned about SkinEffect, when with increasing frequency the current does not really flow throughout the entire volume of the conductor, but moves to the surface. That is why radio frequency cables are made of copper-plated conductors (steel core with a copper coating), or even hollow (feeders). But electric cables at a frequency of 50-60 Hz are not affected by Skin Effect in any way.