Light bulb pulsates while switched off!!

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gingerw140
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Light bulb pulsates while switched off!!

Post by gingerw140 »

Hi

I have noticed since changing my bedroom ceiling light to an energy efficient bulb it pulsates whilst the light is off.

I have only noticed it when the room is completely dark (normally lying in bed!) and that every 8 - 9 seconds it dimly comes on and then goes off in a split second. You dont notice when you look directly at it, more so out of the corner of your eye.

Its probably been doing it all the time, but only noticable since changing to these new bulbs.

Any ideas why this maybe happening? As a complete electrics novice, I have no idea!

Thanks

Nicki
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ultimatehandyman
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Post by ultimatehandyman »

Hi Nikki,

Welcome to UHM :hello2:

is the Lamp controlled by a special kind of switch or is it just a regular on off type switch like this?-

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gingerw140
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Pulsating bulb

Post by gingerw140 »

Hello

Its the same type of switch that you have shown. I have taken a photo of the wiring but unsure at the moment how to upload. However it has one red wire going to the top terminal (? - not sure if that is the correct word!) and a black wire going to one of the two terminals at the bottom (L2). I will try and load the photo for you to see.

Thanks!
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Post by ultimatehandyman »

I'm wondering if the wire has been wired incorrectly and the light switch is disconnecting the neutral instead of the live wire :scratch:

Hopefully one of the sparks will know if this will make the lamp flicker like you say.

Or perhaps the actual lamp itself is at fault
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sparkydude
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Post by sparkydude »

Hi dont worry nikki, it is a normal thing with low energy fluorescent lamps, they take very little voltage to make them start trying to illuminate, when cables are run in parallel to each other, just clipped next to each other in a normal house their is an effect called inductance , this means that the volatge running through the other cables can be induced into the cable which is 'dead' in your case the light cable. this voltage is only very low, below 10V normally, but this can upset the poor little fluorescent lamp and make it light up a small amount. Some types of energy efficient lamp are worse than others for this. try buying a reputable make and see if this makes any difference.


Nick
If it isnt broke dont bloody touch it until it bloody well is and if it is broke then make drawing of the connections before you remove the broken one and replace with a new one LoL
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Rich-Ando
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Post by Rich-Ando »

well, you could take Nick's professional answer as the most probably cause of it. however, i would certainly ask "have you a poltergeist?" :lol:
gingerw140
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Ghost light bulb?!

Post by gingerw140 »

Thank you so much for your responses, i was worried something seriously was wrong! I believe I may have lowered myself and bought a quality Tescos bulb so I may give a more reputable make a try. As for a poltergeist.....mmm....not too sure...it is an old house......

:hiding:
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Rich-Ando
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Post by Rich-Ando »

nahh i think you are more than safe :thumbright:
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