Double grid 12V and 220V?

[Remundo]

220V equipment (sockets, wires and circuit breakers) do not pose a major safety problem at 12V provided they do not exceed the currents expected at 220V. And these limits are small, for example 16A under 12V only gives barely 200 W available

Circuit breakers, on the other hand, theoretically require DC models (rarer and more expensive), but personally I have used ACs which correctly cut off the current up to a few tens of amperes, including continuously.

For DIY outside or in a cabin, you can get by with it, but for installation in a house, I would advise against these approximations because the risk of fire/major disaster is too high.

I rather agree with Forhorse's arguments, I'm not enthusiastic about the "generalized" 12V that you promote with a lot of energy.

220V is a standard much more suited to homes and moreover the majority of household appliances are designed around this electrical choice.

On the other hand, there are now so many "inverters", namely mini-12V DC to 220V AC converters, that I do not find it very appropriate to install a heavy network of 12V cables, including on an isolated site.

[Keanus]

So there...Bravo Remundo: these are exactly the kind of details that you delivered that I expected from this forum a little dull on the technique.

Except that it's 192w out of the 200 you give. But don't quibble.

The interesting thing that you have just brought up is to be able to section both in AC and in DC because I admit, I have never tried the DC/AC mix. Respect for standards which is precisely in the image of colleague Marc Gironce and his little autonomy manual which demonstrates the usefulness of 220v sockets for circulating his 12.

Glad to hear that you were able to see that it works well without any problem: it's exactly this kind of detail that I find constructive.

Where we differ is on the more dominant use of 12v in homes, but as I have not specified everything, I would like to build a home based on isothermal maritime containers based on 2 to 3 modules of 30M2 mounted on 2 semi trailers.

This will make it possible to understand that given the distances to be electrified, the nomadic use that I wish to give to my home without being a simple camper van, is right between what Marc did in his house.

And whatever the case, I repeat it for the umpteenth time, using your own solar electricity at its native voltage remains the most efficient way of consuming and no one can prove the opposite, including taking into account Joule effects. which must be compared to conversion losses.

Far be it from me to put efficiency ahead of reliability and if that were the case, I would put reliability first. But let's be clear: by taking 1v as the main route of consumption, in addition to the good efficiency of consumption, we find an electrical system without transformers, therefore more reliable and less energy consuming for the same service provided.


So I come as an Ex Real Estate Agent "to Closing" by asking you 3 simple questions Mr. Remundo:

- If we consume without first converting our production, are we closer to the energy efficiency of limited production or not?
- If we shunt the transformers, are we not limiting the number of electronic components and thereby the risk of breakdown?
- Simplifying a system by limiting the number of its components, does it not simply increase its reliability over time?

If you answer at least 2 of these questions in the affirmative, you deduce what I think, you support my idea of ​​producing and using the production in its original state.

The rest are just adaptations.

Finally, I am totally opposed to "Mini converters" or "mini inverters" which are the same thing but with another language, for 2 reasons:

- Their extremely questionable energy efficiency (we are far from Victron quality at 3% loss)
- Their multiplication proportional to the number of consumers, thus multiplying potential losses and breakdowns.

Using 220v must, if proof is still required, remain the prerogative of large consumers whose power cannot be conveyed without a major increase in voltage.

To come back to "small converters", I remain fierce about this option: what must be observed is the maximum instantaneous power of the consumer. In short: below 200w as you mentioned, if the consumer requires more than 12v in secondary (21 for example), it will be more efficient to provide him with 12v via a voltage booster rather than giving him 220v which it will necessarily transform into its secondary voltage closer to 12v than 220v.

I have the impression of breaking down an open door or that those who stick to the dogma of the sector forget too quickly: focusing on the needs and use of the end consumer remains the basic logic that no one can technically contradict.

Finally, it is the question of "heavy 12v wiring" that you mention which is technically obvious, that I concentrate my thoughts on:
out of the question of running 12v wiring like 220v in walls whose nooks and crannies would lose linear space.

No...My vision is like the halogens that I have at home: 2 lines 20 cm from the ceiling drawn between 2 walls that can cross partitions (therefore rooms) onto which small jaws are plugged. "piercing screws" of the cables to make the connections by rigid bars which lead to the screwed plate connectors on which the small 20w halo lamps are connected (yeah, it's still incandescent, the 3w LEDs don't bring me any the heat I want).

We are therefore still on 12v via a 220v transformer and I have had this lighting for 20 years, the transformer being a 200w, I only have 2x20w connected to it.

The straight line being the shortest way to connect 2 points, transpose the system of my halogens powered by cables stretched between 2 walls, on 32 mm2 cabling to supply consumers in 6mm2 and 192w max from this centralized line .

There's nothing exceptional: I'm just rewiring my low voltage halogens powered by 220v and I don't know why but the principle is as simple as it is practical, as functional and flexible (well yeah it's cable stretched like a wire laundry), my brain likes it without me being able to say why exactly.

Centralization, flexibility of the stretched cables, no other connector than the small clamping/self-drilling screws which allow the juice to be taken over the entire length of the cables, anti-short circuit safety, simplicity that is difficult to improve, modularity of the tension of the cables including every centimeter becomes a possible feeding point.

I don't know how to explain it but I love my cables stretched to power my halogens because you can't make the connections shorter or more versatile.

So of course, I have never seen this kind of screwable micro jaws adapted to a 32mm2 cable for example, but the principle in small on my cables which must run on 3 mm2, is completely transposable to the larger one.

It is the principle which is good and transposable, which is not visually annoying, which remains particularly accessible, solid and reliable.

It's a bit like hanging on a branch: one or more lifelines on which carabiners plug into them over the entire length.

In summary, running 2 32 mm2 cables along the length of the house with holes in the partitions would allow all the electricity to be distributed at low voltage to be distributed over the absolute minimum length with a wiring section adapted to the power of the consumers to be connected and of course, secured by car-type plug-in fuses, adapted to the useful amperage.


Marc Gironce's idea in his manual is funny, not that stupid, but given the routes of the cables in the partitions, it is more complicated and ultimately the length of the cables will be greater, the accessibility less and the less easy connections to make.


Once again Remundo: if you answered my 1 questions with 3 affirmatives, your answers themselves confirm the interest of a 2v home network. However, it is its deployment which must also remain efficient and economical in terms of the necessary materials.

The pitfall of mini converters is their reliability, their consumption, especially if ultimately the consumer to be supplied uses a voltage closer to 12v than 220v.

I know that you understand what I'm saying, that I'm breaking down open doors and rehashing outrageously, but I have no choice: to make myself understood well is to be sure to be interpreted correctly and to obtain answers. technically reliable without reasonable doubt.

It is not a visceral opinion that I wish to bring out here, but a well-informed technical opinion with regard to technical contexts and situations which, even if they are not common, can prove to be the best choices for energy efficiency. .

It is THE basis outside the usual dogmas in which we are all immersed, that Marc and his autonomy manual on the use of 220v sockets to pass his 12, allowed me to consider leaving my intellectual comfort zone without, in my opinion, due to insufficient security, making people adhere completely.

And I am delighted Mister Remundo that you endorse the technical possibility that Marc brought in his manual, even offering him 8 watts too much

In this very case you have reassured me in your sufficient knowledge, but above all in your ability to break away from dogma while minimizing to "barely 200w available" which is of course a technical fact to be remembered in all circumstances as being the limit.

To finish my dear Remundo, in my capacity as a former website creator with the powers of Super Admin, you deserve in my eyes, your capacity as moderator of this forum that I didn't know until 1 week ago



I'm curious to have your opinion on Marc's manual (I put the link at the bottom of my message saved on my web server), I haven't read everything yet, don't have a very specific opinion yet but this sharing that he made already deserves a good mark, because it is a sharing of ecological innovation, a sharing to allow others to make their way on the long journey of autonomy and its slogan: "No freedom without autonomy" that he put in the title, I really like because of the universality that he introduces.

And it is the universality of 12v in terms of low voltage that I believe in, in which he laid the foundations of his little work implemented in his own home.

If there are things in which I think they will prevail, it is the massive use of solar power, electrostatic storage, and greater use of low voltage to meet human needs, against a backdrop of progressive disappearance of fossil fuels, a disproportionate increase in electrical energy will become the most used energy but will have to compensate for the loss of taxes on oil and nuclear technology on fission will not be the long-term solution on the “carbon-free pilotable”.

While waiting for the ITER merger, we have no other choice than to innovate in renewable energies, but above all to innovate to best consume these green energy productions.

Even ITER and its potential technological leap in fusion will not be able to stand on its own given the heavy electrical inputs necessary to get it started.

Which amounts to saying that without fission, melting point is possible. Which amounts to saying that fission power plants will continue and that to limit their number, we will all have to improve the productivity of renewable energies and their storage in order to offload fission power plants so that they can at all times, at all times, remain the starters of fusion power plants.

As for the advent of this merger which will take place in France (cocorico) all of my Food Truck clients, who are "teacher-researchers" in physics and astrology/planetology (IRAP, CNRS, LAAS, Cesbio, CNES and I'm going on), told me that the merger for them won't happen before 2050 "if we're lucky"...

And it is in 2050 that we will all have to be neutral in Co2...With or without fusion, with or without fission. We will need to have a controllable means that can replace intermittent green energies if necessary.

We will have to produce more solar energy, we will have to use it better.

And this is what I am studying with my second Proto based on solar/Super Caps while reinventing, if possible, the consumption circuits on the low production voltage.

A squaring of the circle that seems to me possible to reason about.

Best regards - Pascal.