Home 230V Light Switch Installation: Phase or Neutral Wire? Electrician Opinions Divided

Hello. I have a very banal question, but I could not find a clear answer to it. I asked experienced electricians and their opinions were divided. Namely:

- In a home 230V installation, the light switch (room lamp) should be mounted on the phase or neutral wire ??

It is obvious that in both possibilities the system will work, i.e. turn the light on and off, but which solution is correct ?? are there any rules that regulate it ?? Because when I once asked a few electricians, this question only caused me to stab between them because some said so and others and I did not get a clear answer.

Thanks in advance for your answers and best regards

Damian

The phase always disconnects !!!!!!!!!!!!

As a colleague Jacur wrote. We always release the phase through the switch. Firstly, for safety reasons, if we disconnected N, we have a constant tension in the lamp. Secondly, disconnecting N creates overvoltages.

Of course, on the phase for two reasons: firstly, for safety, if you turn off the N, there will always be a phase on the lamp, which can be dangerous, for example when replacing the bulb, secondly, if you want to install an electronic switch, you will have problems with it on N. It is similar with fuses, which are always mounted on phase.

And these experienced electricians, what do they do on a daily basis?

Disconnecting the neutral wire when there is voltage on the phase wire is - to put it mildly dangerous, as colleagues have noticed.
See that if, for example, the lamp is in phase and the neutral wire is disconnected, all the working elements of the device are at the network potential. Both those connected "from the phase side" and those "from the neutral wire side" - because in such a situation the bulb is a resistor connecting the connected phase line with the unconnected neutral wire line.

In such a situation, it is best to "save" a little more and instead of a 3-wire installation (L, N, PE), give a two-wire one, and connect the metal lamp housing directly to the neutral wire in it. Of course, the light connector in the N wire is also recommended.


So a bit different from the topic:

Quote:

Secondly, disconnecting N creates overvoltages.

Maybe a friend develop this thread?

Well, so my opinion is confirmed.

I heard opinions from the zero switch because if someone touches them with wet hands ... well, but as you wrote above, the network potential comes to the switch.

The second opinion is that if we break the phase, it will spark and zero will not, I do not agree with this, but maybe my colleague robebi78 will explain to me what is the matter with overvoltage.

Yes, as an explanation. I am not a complete layman in these matters, I only asked as a confirmation of my assumptions

Thanks for the answers

Quote:

I heard opinions from the zero switch because if someone touches them with wet hands ...

In places where there is a probability that someone will touch it with wet hands, connectors with an appropriate IP protection degree must be used. In addition, it is worth considering installing an RCD. Unfortunately, it costs a little, but it can save your life.

I recommend showing your friends at least THIS skimpy article

Interrupt N can be the cause of the so-called. switching overvoltage, especially if the loads are capacitive or inductive, e.g. lighting fittings with chokes. This results in damage to the device - when it does not have overvoltage protection or shorten its service life.
Secondly, interruption of N in the power supply (loosening or burnout of the cable in the switchgear) results in the appearance of inter-phase voltage in single-phase sockets. In order not to be a loudspeaker, I will quote a real-life example:
Reverse command - we are to attach an additional circuit to a 3-phase box (for even load distribution) supplying single-phase sockets in several rooms to which computers were connected. Unfortunately, they have not been turned off. The power supplies are damaged.
Breaking the N wire while the device is running (the phases are still running) is not very wise

Well, yes, between the phases will appear on the computers then, but it will spread over 2 computers, more or less half (depending on the power of the power supply), so theoretically nothing should happen. But only theoretically. But it is true that the N conductor does not disconnect, always in phase. In addition, I know that older electricians often give N to the switches, once I met in one room that in the dark, after turning off the light, you could see that the "energy-saving" bulb was barely glowing, the reason was probably bringing the phase to the bulb and some small current leakage somewhere .

No electrician will not put the switch in the N conductor, and even more so in the PEN. I emphasize an electrician and not someone who considers himself a professional because "he has already changed the bulbs in the chandelier twice"
The glowing of energy-saving light bulbs occurs very often when using switches with backlight. A neon lamp connected in parallel to the switch contact allows sufficient current to flow.

Well, that may be right, because there were illuminated switches, but I'm not 100% sure. As for the "electricians" you are right.

Quote:

I asked experienced electricians and their opinions were divided

I would love to meet these "electricians". I am interested in their professional experience.

Quite a common patent of ship electricians - but they have other installations there and they do not know [?] What a neutral ...

Hello.
The switch should be mounted on a phase conductor!

patryk-84a wrote:

In addition, I know that older electricians often give N to the switches, once I met in one room that in the dark, after turning off the light, you could see that the "energy-saving" bulb was barely glowing, the reason was probably bringing the phase to the bulb and some small current leakage somewhere .

In the past, fuses were also used on both phase and neutral conductors, which was a "mistake" and resulted in many misfortunes. Until now, it happens that such installations are found in old tenement houses.
Fluorescent lamps can glow slightly in the dark, also when there are no neon switches, when there are switches on the neutral wire. The capacitive currents flowing into the environment are simply enough for fluorescent lamps, especially when the luminaire (housing, chandelier) of the fluorescent lamp is grounded.
Greetings.

Quote:

The glowing of energy-saving light bulbs occurs very often when using switches with backlight. A neon lamp connected in parallel to the switch contact allows sufficient current to flow.

But if you put a small resistor in the luminaire of such a fluorescent lamp that does not allow the capacitors in the fluorescent lamp to charge sufficiently, the problem would be solved by itself

[quote = "mrrudzin"]

Quote:

But if you put a small resistor in the luminaire of such a fluorescent lamp that does not allow the capacitors in the fluorescent lamp to charge sufficiently, the problem would be solved by itself

Interesting way of thinking.
Demonstrate it in a schematic (it can be block-based).

In the diagram?
Resistor plugged in parallel to the lighting fixture. The entire scheme :)

Current flows through the resistor and neon lamp in the fitting (as someone mentioned above). This current causes charging the capacitor in the fluorescent lamp to the voltage sufficient to start the converter powering our light source. As the energy is supplied to a limited extent (not sufficient for continuous lighting of the fluorescent lamp) - the lamp flashes for a moment, consuming the energy stored in the capacitor and the process starts all over again.

In better compact fluorescent lamps, this problem was solved - in parallel with the capacitor by mounting a 180 ~ 220 kOhm resistor. It prevents the capacitor in the fluorescent lamp from charging to such a voltage that the inverter starts. Why is this happening, I don't think I need to write anymore.
Well, it happens in the better ones. In these worse - ladybug, real and other inventions - not only the quality of the light is tragic, but also the above-mentioned resistors are missing (costs are cut at every step).
In order not to rummage in the fluorescent lamp itself, it is enough to connect the above-mentioned 2W resistor in parallel to its terminals and the problem should disappear.