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RobP
15th December 2006, 11:15 AM
Hi all
In another forum of which I am a member, two people have reported compact fluorescent lamps which flicker/flash very faintly when they are not turned on. The interval is about one second in one case and six to seven seconds in the other. The effect is very subtle and can only be seen in total darkness. Has anybody here heard of or come across this phenomenon?
Thanks
Rob

SilentButDeadly
15th December 2006, 12:37 PM
Not surprising. All of the CFL's have a capacitor or two inside as part of the circuitry of the starter. Capacitors are broadly a form of battery and they discharge when not under power. Perhaps what people are seeing is the capacitor discharging under limitations dictated by the circuit design (which might explain the flashing)

RobP
15th December 2006, 01:18 PM
So the effect should diminish as the capacitors discharge but apparently, what these people are seeing is continuous. I have fifteen CFL's throughout my house and I have never seen this effect.

Groggy
15th December 2006, 01:42 PM
Do they have high voltage power lines nearby?

Malibu
15th December 2006, 05:52 PM
Do they have high voltage power lines nearby?

It sounds to me like a HV induced problem. It's something that's caught me a couple of times, but not on lighting circuits.

cross
15th December 2006, 06:17 PM
I have a compact fluro in my bedroom and have noticed the flickering when its pitch black. Usually after the light has been on for most of the night. My guess, like others, is the capacitors discharging. The flashing only lasted for a short period and did not continue all night.

savage
16th December 2006, 09:21 PM
Yes!..I have the same effect with two wall lights in the loungeroom, funny thing is we spend all of our time in the family room and seldom turn these lighte on. We have this type of globe throught out the house and these are the only two that do this?..

We have no HV lines near by that I am aware of unless you count the ones nearly 1/2 a K away. I asked my electrician and he said it was just a side effect of this type of lighting and not to worry about it, also it only happens under a particular set of circumstances, not all will do it.

Ashore
16th December 2006, 09:42 PM
Get the household earth checked
Are they all on the same circuit if so check the the switch is switching off the active and not the neutral
And if on the same circuit check the all the lights are corrected with the active on the light to the active on the circuit.

savage
16th December 2006, 09:51 PM
Get the household earth checked
Are they all on the same circuit if so check the the switch is switching off the active and not the neutral
And if on the same circuit check the all the lights are corrected with the active on the light to the active on the circuit.

Good advise, I had mine checked out, and if anything is odd with electricity get an electrician in to look at it, better be out of pocket a few buck's than risk yourself or a family member. I was lucky as I had my bloke there doing another job and he looked at it for nothing.

Barry_White
16th December 2006, 11:18 PM
We have a nylon bedspread that does that in the dark when you flick it backwards and forwards.

Do you think I should get a sparky to check it out?

savage
17th December 2006, 12:01 AM
We have a nylon bedspread that does that in the dark when you flick it backwards and forwards.

Do you think I should get a sparky to check it out?

No!..But I'd be having a few words with the chambermaid!....:D :D :D

Eddie Jones
17th December 2006, 10:35 AM
House Goblins?

savage
17th December 2006, 06:47 PM
Electric Blanket!....:eek: :D :D