Stair Switch Issue: One of Two In Corridor Not Turning Off Light Bulb - Sudden Malfunction

Hello
I have a problem with the stair switch. Two stair switches in the corridor, one lamp (ordinary light bulb). After turning on the light with one switch, it cannot be turned off with the other (the bulb seems to tremble, but it is still on). The second switch, on the other hand, operates only with one setting of the first.

Everything has been working fine so far, the problem appeared suddenly, overnight, there were no changes in the installation in the meantime, I did not disconnect anything for painting, etc.
My first thought was to damage the switch, I bought a new one, replaced it (identical switches, wires connected the same) the problem is still there.

Below I put all combinations of switches, the letter "P" marked which wires are live.


From what I have read here on the forum, I already know that the wrong colors of the wires were used (this is how the installation was done) - but this is not the cause of the problem

Probably the brown wire in the switch 1 is the main current wire (constantly live, the same contact is connected to the wire leading to other rooms).
According to the diagrams that I found on the internet, the brown wire from switch No. 2 should lead directly to the lamp, but after it is completely disconnected, I can turn on the lamp with switch No. 1.
A standard 3-color wire is connected to the lamp, when the light is on, the voltage is always on brown.

I do not know if it matters, but in the box behind the switch No. 1 I have connected cubes:
- 3 blue wires
- 3 green-yellow wires
- 2 brown wires

What could be the cause of the problem, what should I check next?
Thanks in advance for your help and any suggestions.

Regards
Mark

* protective conductor not included

marhir wrote:

I marked with the letter "P" which wires are live.

How did you check for voltage?

zbich70 wrote:

marhir wrote:

I marked with the letter "P" which wires are live.

How did you check for voltage?

so-called sampler "neon"

I can also try to check with a multimeter, but I do not know which of the wires to connect the "neutral" end of the meter

marhir wrote:

so-called sampler "neon"
I can also try to check with a multimeter, but I do not know which of the wires to connect the "neutral" end of the meter

Therefore, I do not take advice.
I suggest you call an electrician.

zbich70 wrote:

marhir wrote:

so-called sampler "neon"
I can also try to check with a multimeter, but I do not know which of the wires to connect the "neutral" end of the meter

Therefore, I do not take advice.
I suggest you call an electrician.

Normally, in a simple situation with some ordinary socket or lamp, I can measure it without any problems, but if I only have three wires, the neon light is on all of them, I didn't risk it.

Probably one of the switches is defective. There is nothing to argue here, you just need to call an electrician to fix it because you may not be able to do it yourself, especially since you do not have experience as you write. If you can turn off and on with one and not with the other, it means that the other can be damaged, but not necessarily that it must. proposes to replace the suspect circuit breaker with another working one. FIRST ONLY: Turn off the "plugs" so that there is no current in the circuit, and then just to be sure, check if there is any. The FIRST basic step in the work of an electrician for health and safety reasons is the OBLIGATION TO CHECK for the presence of voltage in the circuit. Then you can start trading. Now like this: - on the new stair switch you will find three "grooves" for wires. You put the phase in the groove marked in red, and connect the other two wires to the rest. If this is the layout as everywhere in the stairway, then the phase should come in blue. That's why it's better to double check how to get electrocuted once remember! And write what you came up with. I am curious. Good luck!

Radiowiec 2 wrote:

Probably one of the switches is defective.

Let's assume not?

You have to start somewhere. I don't think I got it right away.

With so little information, one can only speculate.
Most likely, in the second switch, the blue and brown wires should be swapped.
Probably the author does not tell us everything or even misses the truth. The bulb is not ordinary, but energy-saving. Or did the problem start after it was replaced?

It's funny that an old 15-watt light bulb is best suited for such "measurements".

marhir wrote:

I have a problem with the stair switch.

A question to the Authority. What is the stair theme this year? Why do writers, when accepting the rules, have it in a big.....?

Radiowiec 2 wrote:

You have to start somewhere.

You're right I suggest starting with ZPT at the high school level.

@ Resistor 7. I will say this - we are not there and we do not know what is really there. It may be as Colleague writes earlier (changed endings), but since it worked so far and stopped without human intervention ... And kindly, please, humbly refrain from sarcasm like middle school c'no? Because you don't know me, you don't know what and when I finished c'no? And at what level. The fact that he writes colloquially like all of us does not mean that I can't do anything and I'm the proverbial jerk, because it's not true. I was finishing something there, some diploma "got along" on the way and some little knowledge but I have. After all, this is a general discussion, not some scientific symposium. C'no?

Buddy Radio guy 2, but I didn't write about you. I just quoted your words. In post #2, the connection method is given in picture writing. Of course we don't know the cause of the "sudden" failure. So it's pointless to discuss this over the internet.

@Resistor 7 Okay sure! but it's hard to be infallible from a distance. don't you think? I'm just trying to help. Is it wrong? And the author of the topic will do what he thinks anyway, because firstly we are too far away, and secondly, some things cannot be solved without a specialist present in a given place.

mar_uda wrote:

Most likely, in the second switch, the blue and brown wires should be swapped

I checked, it doesn't help.

mar_uda wrote:

The bulb is not ordinary, but energy-saving. Or did the problem start after it was replaced?

The bulb was and is energy-saving - it was not replaced (and it worked), when it stopped working, I also checked it on another (LED) - and it's the same.

opornik7 wrote:

What is the stair theme this year?

opornik7 wrote:

In post #2, the connection method is given in picture writing.

I have read previous topics, diagrams, on this forum and on others, including the diagram from post #2 and 2 other connection diagrams, including the one attached to the switches. Everything seems to be fine, but it doesn't work.
The problem is that I do not put a new installation, but I have it already laid "as is" and so far working. I do not know how the wires run except for the ends protruding in the switches and in the lamp. (over the weekend I will try to check the transitions between the individual ends of the wires to make sure that nothing is changed along the way).
Of course, I can break two walls and a ceiling and lay new wires according to the scheme, but then my wife will throw me out of the house ;-)

opornik7 wrote:

Of course we don't know the cause of the "sudden" failure.

And that's the problem that I don't know either (one day it worked, the next it didn't).
I was also wondering if something had flooded somewhere or something had not bitten through the cable under the ceiling.

Radiowiec 2 wrote:

some things can't be solved without an expert on site

I also take this option into account, but I wanted to see if I could do something myself, especially since at first it seemed to me that the solution to the problem would be to replace the faulty switch, later that it may be something simple - common - what with the help of the Forum I will do it myself while learning something new.

One more question. Have you checked both switches with an ohmmeter to see if they are switching properly? because visually they may be impeccable, but after checking it turns out that this is not the case. Be kind and check it out.

marhir wrote:

My first thought was to damage the switch, I bought a new one, replaced it (identical switches

Radiowiec 2 wrote:

one more question. Have you checked both switches with an ohmmeter to see if they are switching properly? because visually they may be impeccable, but after checking it turns out that this is not the case. Be kind and check it out.

Checking the "transitions" between the wires with a multimeter with a 9V battery makes as much sense as checking for the presence of voltage with a neon lamp in a long circuit with a converter in the middle.
Since we are still having fun, I suggest replacing the light source with a regular bulb (glass bulb with a tungsten filament and vacuum, no LED or other energy-saving lamps) for the time of "measurements". With such a receiver on board, you can repeat the "measurements" made with the neon lamp from the first post.
It is possible that with an ordinary light bulb in the circuit, the problem will magically disappear by itself.

@Mar$-uda You may be right. After replacing the bulb, the problem may disappear. What if not? Do you have any further suggestions?

Qrna, gentlemen, give it a rest. Unclip the stairs, unclip the luminaire. Identify L, N, identify the correspondence veins and then, based on the drawing from post #2, re-lace the installation. If you don't understand what I'm talking about, go get a coffee. 5 minute job for an electrician. Finish, gentlemen, save the shame.

What else needs to be identified? The description is in the first post:

marhir wrote:

I do not know if it matters, but in the box behind the switch No. 1 I have connected cubes:
- 3 blue wires
- 3 green-yellow wires

3 wires each, i.e. power supply, going to the next box and to the lamp.

marhir wrote:

- 2 brown wires

And here is the connection of the brown one from the lamp to the brown one from the wire between the connectors.
The other two wires in the cable between the connectors are blue and yellow-green, which are used as correspondence.
In case anyone asks where is the phase leading to the next can, it's here:

marhir wrote:

Probably the brown wire in switch 1 is the main current wire (constantly live, a wire leading to other rooms is connected to the same contact) .

That's all identification. The drawing of "measurements" from the first post only confirms this.

Over the weekend, as suggested, I checked additional things:
- replacing the bulb with a "normal" one - does not change anything
- replacing the lamp with another - does not change anything
- checking with a "neon lamp" on a regular bulb - nothing changes
- checking the transitions with an ordinary multimeter confirms that the wires are laid out as in the diagram in post #2 @Arturo2005 and as described in post #21 @mar_uda

And now a curiosity:
After disconnecting all switches (bare wires sticking out of the wall on both sides):
- blue and green-yellow (correspondence) wires, according to the meter, there is no transition between them,
- after connecting the voltage to the green-yellow on the blue (not connected anywhere) there is voltage (neon lamp and 230V on the multimeter)
- in turn, after connecting the voltage to the blue - on the green-yellow (not connected anywhere) the neon lamp shows the voltage, and the multimeter does not (0V - I take into account that maybe I am measuring something wrong, although I made the measurement in the same way as in the sentence above)

Author - unfortunately your answers are so imprecise that it's hard to deduce anything from it. Voltage is the potential difference between two points, and you apply one end of the meter to the wire, and the other ... well - it is not known where.
Better put down the meter and the neon lamp, because they only bring confusion.

If the "ordinary" bulb works the same as you showed in the picture in the first post, please add a clear photo of this "ordinary" bulb.

Disconnect both switches and check several possible connections (of course, all connections and modifications must be made with the power disconnected!):
1. In the first box, connect the brown and yellow-green wires.
1a) Does an ordinary bulb light up when the wires in the other box are disconnected?
1b) Does an ordinary light bulb glow when you connect the yellow-green wire to the brown wire in the second box?
1c) Does an ordinary bulb light up when you connect the blue and brown wires in the second box?
2. In the first box, connect the brown and blue wires.
2a) Does an ordinary bulb light up when the wires in the other box are disconnected?
2b) Does an ordinary light bulb glow when you connect the yellow-green wire to the brown one in the second box?
2c) Does an ordinary bulb light up when you connect the blue and brown wires in the second box?
3. Does an ordinary bulb light up when you connect the brown wire to the cube with the two brown wires in the first can?

If ONLY questions 1b, 2c and 3 are answered YES, also attach clear photos of the switches with visible terminals to which you connected the wires.

I hope that we haven't exhausted the patience of the moderators yet, because we have probably reached the level of elementary school or even kindergarten. Unfortunately we are moving down.

mar_uda wrote:

You apply one end of the meter to the wire, and the other ... well - it is not known where

to neutral N blue

mar_uda wrote:

then add, please, a clear photo of this "ordinary" light bulb.

mar_uda wrote:

Disconnect both switches and check several possible connections

1a no
1b YES
1c no
2a YES
2b YES
2c YES
3 YES

The cable between the switches is obviously damaged. Probably a short between the blue and brown wires. If it was certain that this was the only damage, one could still be tempted to use a bistable relay, but it is not known whether any structural element is energized in this way.
If there is still a can on the way - you can look there. If not, the damaged section will need to be replaced. Alternatively, you can be tempted to invite an electrician with the appropriate equipment who can try to locate the fault, but it will not be cheap.

mar_uda wrote:

The cable between the switches is obviously damaged.

mar_uda wrote:

it is not known whether any structural element is under voltage in this way

following this lead, I checked everything metal in the corridor, the nail on which the photo was hanging turned out to be the culprit (hammered about two years ago)
Thanks everyone for the tips.