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Lighting at 12 volts in the house - what are the advantages and disadvantages?

 

Lighting at 12 volts in the house - what are the advantages and disadvantages?To an uninitiated person, such a question may even seem strange. How could the idea of ​​using 12-volt luminaires and lamps in residential premises be born when the standard for household voltage in our country is 220 volts? Let's try to figure it out.


Advantages and reasons for the popularity of voltage 12 volts

First of all, 12 volts is an extra-low voltage, considered conventionally safe for human life and health. For this reason, in rooms with a high or increased degree of danger, the use of 12-volt lamps is welcomed by the rules of PUE.

Bathroom, kitchen, outdoor courtyard - these are the places in which low-voltage lighting has always been preferable. And in cramped and damp basements, it is completely impossible to operate a 220 volt network, and a step-down transformer is required even for power supply portable power consumers.

Wiring 12 volts does not require a reverent attitude, allows you to save on protective materials, such as corrugated pipe or cable channel. Anyway, the soul is much calmer when you know that the maximum that can happen in your lighting circuit is a ridiculous short circuit with the failure of a cheap transformer or the operation of a protection.

Fires, serious electric shock to people in the lighting circuit of 12 volts are practically excluded.

12 volt lighting in the houseBut there is another reason why 12 volt lighting circuits have gained popularity in residential buildings and apartments. It's about the emergence and distribution spotlights.

These lamps radically changed the views on lighting as such. Therefore, they acquired the name "point", because their light should literally come from one point. And the traditional incandescent lamp, which was popular at that time, can only be called a point with a big stretch. Whatever you say, this is still an impressive bulb, if only, of course, its power is at least 60 watts.

Therefore, the idea arose to use compact spotlights halogen lamps. Bulbs of halogen lamps contain not only inert gas, but also vapors of some halogen, for example, iodine. During the evaporation of tungsten from an incandescent filament, a halogen interacts with metal atoms to form a tungsten halide. This same halide again settles on the filament, decays on it from exposure to high temperature and returns the filament to pure tungsten.

Thus, the wear of the filament of halogen lamps is very small compared to the wear of the filament of conventional lamps. This makes it possible to heat the lamp thread to a higher temperature, at which the smaller lamp shines brighter. It became possible to create a bright and durable compact halogen lamp.

It was then that it turned out that really low-voltage compact halogen lamps, the filament of which is thicker and designed for more current, are really durable and reliable. Therefore, the idea was implemented to install in the household lighting circuit fixtures with 12-volt halogen lamps, powered by compact low power transformersusually electronic. A similar scheme was already very popular when modern and reliable 220-volt compact halogen lamps began to be mass-produced.


So, what are the advantages of 12 volt household lighting networks? They consist of:

- safety and, as a result, the possibility of operation in hazardous areas;

- less stringent requirements for wiring;

- the absence of the need for qualified maintenance (a 12-volt lamp can be installed even by a person far from electrical engineering - there is no risk to health);

- the possibility of implementing additional lamp protection against overcurrent and voltage due to the transformer.



Disadvantages of lighting at 12 volts

12 volt lighting in the houseBut 12-volt lighting has its drawbacks. The same transformer is an additional element of the circuit, which, firstly, has its own efficiency, and secondly, complicates the circuit, reducing its reliability. In addition, the transformer must be hidden somewhere, providing it with cooling. It must be selected according to the total power of the fixtures with the necessary reserve, otherwise it may not start or quickly fail. In a word, a transformer is already a whole mass of minuses.

But the shortcomings do not end on the transformer. Another minus is that a low voltage network with equal power consumes more current. A larger current is a greater voltage drop across the wires. Therefore, when installing 12-volt lighting lines, you have to think about the length of the conductors from the transformer to each lamp being approximately the same. Otherwise, lamps located further down will shine less brightly.

Thus, the disadvantages of lighting at 12 volts are reduced to installation difficulties due to losses in the wires and the need to introduce a transformer into the circuit.

Alexander Molokov, https://env.electricianexp.com

We recommend reading:How to choose a wire cross section for 12 volt lighting networks

See also at bgv.electricianexp.com:

  • Incandescent lamp soft start device
  • Home-made step-down transformer for damp rooms
  • The specifics of the installation of lighting lines with electronic transformers
  • How to choose a bulb for recessed spotlights
  • The use of spotlights

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    Comments:

    # 1 wrote: | [quote]

     
     

    Well, about the fire hazard, not everything is so safe. Cars burn for a sweet soul. Take into account the cross-section of the conductor is necessary.

     
    Comments:

    # 2 wrote: Sasha | [quote]

     
     

    And where do the cars with their on-board network of 12 volts DC, shorted fuse and the absence of any other protection?

    And in the lighting circuits are transformers with built-in overcurrent protection.

    You can foolishly burn anything.

     
    Comments:

    # 3 wrote: | [quote]

     
     

    A very useful article. The information submitted is high-quality (at the consumer level), and it is up to the person to decide.

     
    Comments:

    # 4 wrote: | [quote]

     
     

    "low voltage network, with equal power, consumes more current" => more voltage drop in the wires => power released by the wire => temperature increase => FIRE !!! Conclusion transformer d / b near the lamp. => Lighting network 220V !!! And there’s nothing to poke your fingers where you should not, without education!

     
    Comments:

    # 5 wrote: Sasha | [quote]

     
     

    Alexander, and when the 220 and 12 volt networks are closed on the same load, for example, on the transition resistance of a bad contact, in which case will the current (and hence the heating) be higher? Have you thought about it?

    Bad contact in the 12 volt network - nothing works.

    Bad contact in the 220 volt network - guaranteed problems.

    And fill in the gaps in your education, at least in order to communicate more clearly. And then I hardly understood your writings.

    And by the way, short circuits and overcurrents for any network are not good. However, a 12 volt electronic transformer simply cannot deliver power in excess of rated power. It will turn off or burn out. This is not a circuit breaker for you, which may not work, or work too late.

    So in terms of protection against overcurrents and short-circuit currents, a 12 volt lighting network will be preferable.

     
    Comments:

    # 6 wrote: Alex | [quote]

     
     

    Tell me, I have a network in a 220-volt apartment, I bought 12-volt spotlights in the market (the seller said that they are the only ones and you can connect halogens to 220-volts and everything works fine). I am not good at electrics, but as I understand it, at a low voltage of 12 volts the current will be higher (for example, a lamp of 100 watts, 100w / 220v = 0.45A 100w / 12v = 8A), i.e.logically, a 12-volt cartridge should quietly withstand a 220-volt lamp, everything is connected at home. But still I understand that something is not right. Tell me, can I be calm or the seller misled me and it is better to change the lights ???

     
    Comments:

    # 7 wrote: author | [quote]

     
     

    Alex worried in vain. The cartridge is the same. The main thing is that the lamp should be 220 volts.

     
    Comments:

    # 8 wrote: | [quote]

     
     

    Such all literate damn it, in this article did not indicate all the advantages and disadvantages of 12 volt lighting. Nothing is said about the wire cross section of 4 mm2 for a 60-watt bulb (only about the same length of the wire), from the fact that these transformers (specifically Chinese) fly out once every six months - a year. And you can also use lighting with 220 volts in the bathroom or on the street (just choose lamps with the appropriate degree of protection IP) or you can use the lights you liked when you liked it (without IP compliance), but then you need to insert an RCD with a cut-off current of up to 30 mA and everything will be OK. 20 years ago, most people used (for domestic purposes) a 220 V network and no one knew about a network with a voltage of 12 V and everything was fine. If all this is done, then tomorrow and 12 V the network will kill someone, transformers and lamps for 0.5 V (200A) voltage and a cable for connecting these lamps from a superconductor will appear at a price of 200 cu for a unit. And still there is a rich dol-eb, and he will buy such equipment, and put it at home ...

     
    Comments:

    # 9 wrote: | [quote]

     
     

    I'm lost right ...

    You can not curse, for starters. Words in Russian are enough without it.

    60-watt lamps for 12 volts do not often come across. And 1.5 squares is more than enough for them. Where did you come up with the four? 5 amperes of everything turns out.

    Are transformers burning? Do not save - take the normal ones.

    And finally: but who obliges you to switch to 12 volts? This is just one of the security measures. Not required. Do not like it - do not use.

     
    Comments:

    # 10 wrote: | [quote]

     
     

    Which are normal? Normal transformers in China do not, and there are simply no Chinese in the market. At the expense of 1.5 squares, instead of 4, I will say that with a difference in the length of the wire of more than 30% from one transformer, the difference in the brightness of the lamps is very visible, from personal experience I will say if 10-15 lamps are connected to one wire ( power of 30-45 W), even with a cross section of 4 mm2, the difference in the luminescence of the 1st and last lamps will be too obvious. If the room is small, then you can try 2.5 squares, and if for example you need to light a corridor 5-8 meters long, then you need to race for a long time so that the brightness is normal.

     
    Comments:

    # 11 wrote: andy78 | [quote]

     
     

    Vitaliy, to select the correct wire cross-section in 12 volt networks, you can use the table of the dependence of the wire cross-section on its length and lamp power. The table itself and recommendations on how to ensure uniform luminous flux of halogen low-voltage lamps are given in the article - How to choose a wire cross section for 12 volt lighting networks.

     
    Comments:

    # 12 wrote: author | [quote]

     
     

    Come on, Vitaly. I also appreciate artistic exaggeration, but not to the same extent. And Chinese trances serve much more than a year. This is also infa from my own experience. China is also different.

    And it’s better not to power the 12-volt lamps with a cable, as you yourself know. One lamp - one wire, and then there will be no differences in brightness. Of course, this is the disadvantage of 12-volt lighting, but no one argues with this.

     
    Comments:

    # 13 wrote: Evgeny | [quote]

     
     

    And if you use LED backlight?
    LEDs do not consume anything at all (relatively)!
    for example, I want to illuminate a section of the site with distance LEDs in the country, as you can guess there are more than 20 meters, can you say this is generally feasible?

     
    Comments:

    # 14 wrote: Author | [quote]

     
     

    Eugene, it will be very expensive. And LED lamps, as far as I know, currently have built-in electronic voltage transformers.And the network will still be the same - 220 volts.

     
    Comments:

    # 15 wrote: | [quote]

     
     

    12 volts at home is good and safe, but do not forget that when the voltage decreases from 220 to 12 V for a 100 W light bulb, the current increases with a fraction of an ampere to ten amperes. And this means it is necessary to use connectors designed for these currents, and the diameter of the wire will need to be significantly increased.

     
    Comments:

    # 16 wrote: | [quote]

     
     

    Vitaliy, it’s not true that in China there are no good transformers, everything is there, but they cost more, so either they are not transported or sold where you don’t go. And if you connect 10 10W lamps to a 100W transformer, then of course it will not work for a long time, since it needs a margin of about 20%, that is, if you connect 7 10W lamps to a 100W power supply, everything will work fine and I think that will not burn ..
    forsign.kz we are engaged in LEDs and transformers for them. All of Kazakhstan takes transformers for street signs and gives a guarantee for them from 1-3 years and nothing works for 5-7 years.

    Alrxds, I understand what I wrote?

     
    Comments:

    # 17 wrote: | [quote]

     
     

    The article is good, I myself have been studying this topic for a long time - out of economy, I generally have power from the battery - there are 220 no - anyway. As for the thick wire type, it’s necessary - I have to say this Hochma to the Japanese. look under the hood of a Japanese car there on the headlight (lighting device) such plump plump wires go and the lamp does not shine weakly, yes ?. education, calculations, blah, blah, blah. there is a saying who wants to look for a way-of an opportunity, and who doesn’t want that excuse-reason. It seems to put the point right. The disadvantages of 12 volts as well as 220 volts are solved by the quality of performance, there is nothing, well, we are looking for components and assemble from them from the lamps the heat has gone - there is no point (saving), LEDs. Good luck.

     
    Comments:

    # 18 wrote: | [quote]

     
     

    He who seeks will find. Bad transformers? Winding yourself and all that stuff! Yes, and not only a transformer is needed - but a full-fledged pulse source. And then the welder will have to wind :)

    Or - bought Chinese, rewound normally, laid insulation, impregnated with BF glue - and that's all. But it will serve as a Soviet.

     
    Comments:

    # 19 wrote: | [quote]

     
     

    There is another drawback of 12V power fixtures in the bathrooms. From moisture, the contacts of the lamp base are scattered, because there is a constant voltage and electrochemical corrosion occurs.

    I made a mistake, the voltage at the output was variable, but for some reason the lamps fell apart in the base, and only in the bathroom (12V).

     
    Comments:

    # 20 wrote: | [quote]

     
     

    I read the article, readers' opinions in the comments and realized: it was not in vain that I did not succumb to the temptation to install 12-volt equipment when repairing an apartment :) For many years of operating 220V wiring, lighting and household appliances, I have never had a serious accident, except for / s due to carelessness or due to a faulty extension cord. I have spot lighting, only 11 lamps with a GU10 base, I used 50W halogens, a year ago I switched to LED. My friend installed 12v wiring in a plasterboard ceiling 4 years ago and successfully changed 3 or 4 transformers, several MP16 cartridges ... Talking about 12V safety is nonsense: how often do we climb to 220V wiring or touch it with a finger under voltage ..? What, does the instinct of self-preservation not turn off the system before the intervention? I understood one thing: the simpler the better, I am for 220V.

     
    Comments:

    # 21 wrote: Dmitriy | [quote]

     
     

    What are 10 amperes per lamp ??? Do you know how to use Ohm's law for a section of a circuit ???
    Here is the resistance of the filament of incandescent bulbs !!!

     
    Comments:

    # 22 wrote: Jorro | [quote]

     
     

    More than 10 years ago, halogen lamps were installed in the suspended ceiling.
    (He suggested using his electrician to save energy.)
    4 lamps for 30 W 12 V, transformer for 150 W.
    That in the corridor, that in the kitchen, everything has been functioning for many years.
    There are no comments on the operation of the 12V network.

     
    Comments:

    # 23 wrote: | [quote]

     
     

    Jorro, I wonder how magically halogens save energy ??? Do they have higher efficiency than incandescent lamps? No - in fact, halogens are also incandescent lamps. They do not heat up at work, using the bulk of the energy consumed precisely for the emission of light? Not too - they get warm, and how. Maybe something else that I don’t know about them? It is unlikely ... Moreover, in the 12 V circuit there is another element that is wasting part of the energy in wasted heat and vibration - a transformer. So what about savings with the help of halogens, especially in 12 V circuits, do not even stutter!

     
    Comments:

    # 24 wrote: Andrew | [quote]

     
     

    Prorock,
    In fact, modern halogen incandescent lamps give out 20 lumens / watt, and incandescent lamps 10 lumens / watt. So halogen energy-efficient incandescent 2 times.

     
    Comments:

    # 25 wrote: | [quote]

     
     

    I have no comment, but questions. I got such a trance WH-1052E-AF for free. Can it be turned on without load? Can I load with a rectifier and with what minimum can it work? Well, the last request. Where can I get a diagram on it?