Glowing fluorescent tube when turned off?

[rawzone]

Photos as requested the switch at the bottom of the photo is the one to the tube, the other switch is to an external light that is now disconnected with the end of the cable terminated with blocks.

Thanks for all responses.

Untitled

• rawzone
• 18 Dec 2011
• 1

Untitled

• rawzone
• 18 Dec 2011
• 1

Untitled

• rawzone
• 18 Dec 2011
• 1

 

[Lectrician]

While the neon screwdriver is not a tool that should be recommended, as this is all you have, can you do a couple tests?

With the fuseboard and the wall switch on, CAREFULLY test to see if the red in the light fitting is live (nice bright glow on the neon), do the same with the black in the light fitting.

Then.

With the fuseboard on and the wall switch off, CAREFULLY do the same tests again.

I would only encourage you to do this if you are aware of the dangers involved with electricity, and realise that you are working on a live circuit. If you feel at all incapable, do not even try!

 

[rawzone]

With the fuseboard and the wall switch ON the screwdriver glowed on the black wire but not on the red wire and with the fuseboard on and the wall switch OFF the screwdriver glowed on the black wire AND on the red wire.

Now I am confused.

Hope that info helps.

 

[riveralt]

From the photographs it looks like you have live and switch live (black with white tape) at the switch.
At the lamp unit you have moved from a switch live(black with white tape) situation to a live(red), neutral(black) and earth (which doesn't have sleeving on by the way).
This means there must be a junction box or terminal block behind the lamp unit.
You will need to check to see how that is arranged - possibly photograph same.
Neon screwdrivers are not very accurate for testing purposes and you may be reaching the point where you need to call someone in to sort it out for you.

 

[rawzone]

I can get into the loft and find the junction box and take a photo of the wiring, will it need testing with the light switch on and off with the neon?

Thanks to all for responses.

 

[riveralt]

I can get into the loft and find the junction box and take a photo of the wiring, will it need testing with the light switch on and off with the neon?

Thanks to all for responses.

It was flameport that suggested one of the possibilities was that the line and neutral were the wrong way around.
Look at the junction box connection here:
//www.diynot.com/wiki/electrics:lighting:single_way_lighting:jbnonharm
This is what I would expect at the jb. You can see how the live, neutral and earth loops are set up. A live (red) leaves the live loop goes to the switch and comes back to the jb as the switch live (in your case black with white tape) - it then goes to the top right terminal changes to red and then goes to the L terminal on the lamp. Similarly, the black (neutral) goes from the lamp back to the neutral loop.
This is what you are looking for - forget for the moment what is live or not because your tester is not the best method of properly identifying it.
If the set up is at shown in wiki then with the power off check that all connections are tight - if they are then there may well be a problem with the actual lamp unit itself.

 

[rawzone]

Went into the loft and located top of light fitting I assume (piece of floorboarding between joist with cable passing through it). The cable headed off in a different direction to the switch with no sign of a junction box so now I am confused.

I have even tried changing the appliance with one from another room and still get glowing tube when turned off, maybe it has always glowed when off and we haven't noticed.

Looks like we will just have to have a lamp in the kitchen until the refurb is done in the new year.

What a puzzler?

Many thanks and much respect to all for help given.

Richard

 

[Lectrician]

With the fuseboard and the wall switch ON the screwdriver glowed on the black wire but not on the red wire and with the fuseboard on and the wall switch OFF the screwdriver glowed on the black wire AND on the red wire.

Now I am confused.

Hope that info helps.

Well that confirms that your switch is switching the neutral, not the live.

There must be a joint box somewhere. Likely under the floor if no loft above?

 

[rawzone]

Hopefully I will find out tomorrow as an electrician is calling in on other business and he has kindly said that he will put a tester on the cables.

Regards to all

Richard

 

[rawzone]

Found out the problem. The live and neutral were coupled the wrong way round on the consumer unit and have now been rectified.Tube no longer glows when turned off.

Thanks to all for help and suggestions given.

 

[Taylortwocities]

Found out the problem. The live and neutral were coupled the wrong way round on the consumer unit and have now been rectified.

Not a good sign on the health of the rest of the installation.
That is a sure sign that incompetent work has been carried out and NO testing was done afterwards.

You should consider getting an EICR (Electrical Installatrion Condition Report) done to see what else needs sorting out!

 

[Lectrician]

I have seen a meter replaced by a meter operator, leaving an install with reverse polarity....

 

[Taylortwocities]

I have seen three consumer units installed with the feeds reversed.

Makes you wonder about testing eh?