Hi;

I've got a three-bulb light in my bedroom. It's one of those which is
attached to the ceiling; and takes three small 40watt bulbs (bayonet
fit). About a year ago, one of them blew, and I replaced it with a
fluorescent bulb of equivalent strength. Then a few months agoa second
bulb went - again, replaced it with a fluorescent. A couple of weeks
ago the third bulb went, and I haven't replaced it yet; but I have
noticed that for about half an hour after we switch the light out, one
of the blulbs flickers, every 5-10 seconds. Not enough that it comes
on; it just looks like a dim flash - one flash each time. A few times
I've woken up at three or four in the morning, and noticed it's
stopped.

No dimmer switches; nothing fancy. Just two light switches, either of
which will turn the light on or off. It seems perfectly normal when
it's switched on. The wiring is quite old, and there's no earth wire;
but I wasn't blowing bulbs every few weeks or anything, I've no reason
to suspect the wiring, other than I can't really imagine what else can
be causing this.

Can anyone offer advice?

Thanks;



Tim

wrote:

noticed that for about half an hour after we switch the light out, one
of the blulbs flickers, every 5-10 seconds. Not enough that it comes
on; it just looks like a dim flash - one flash each time. A few times
I've woken up at three or four in the morning, and noticed it's
stopped.

Can anyone offer advice?

It is a well known problem. You probably have a reasonably long run of
cable to the light that is in close proximity to other live wires. This
will lead to a small amount of coupling between them (inductive or
capacitive); in effect inducing a voltage in the floating switched live.
Every so often a capacitor in the lamp will charge enough to start the
bulb conducting and you get a brief pulse of light which discharges it.

The presence of the filament lamp would prevent this since it would
simply conduct any charge away. As soon as the last one blew you started
seeing the problem.

--
Cheers,

John.

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wrote in message
ups.com...
Hi;

I've got a three-bulb light in my bedroom. It's one of those which is
attached to the ceiling; and takes three small 40watt bulbs (bayonet
fit). About a year ago, one of them blew, and I replaced it with a
fluorescent bulb of equivalent strength. Then a few months agoa second
bulb went - again, replaced it with a fluorescent. A couple of weeks
ago the third bulb went, and I haven't replaced it yet; but I have
noticed that for about half an hour after we switch the light out, one
of the blulbs flickers, every 5-10 seconds. Not enough that it comes
on; it just looks like a dim flash - one flash each time. A few times
I've woken up at three or four in the morning, and noticed it's
stopped.

No dimmer switches; nothing fancy. Just two light switches, either of
which will turn the light on or off. It seems perfectly normal when
it's switched on. The wiring is quite old, and there's no earth wire;
but I wasn't blowing bulbs every few weeks or anything, I've no reason
to suspect the wiring, other than I can't really imagine what else can
be causing this.

Can anyone offer advice?

This has been discussed here several times.
Are they Philips CFLs? Basically they are not too well designed
and the capacitance of the live and switch-wire is enough to make
them flicker.

--
Graham.
%Profound_observation%

This has been discussed here several times.

Blow! I searched with google, but obviously not specifically enough.
Sorry!

Are they Philips CFLs?

Yes, they are. I bought Philips rather than the el-cheapo option
becaus I thought they'd be better designed. That'll learn me!

Basically they are not too well designed
and the capacitance of the live and switch-wire is enough to make
them flicker.

Do I get the impression I might as well just live with it, then? It's
not bothering me, except to make me vaguely worried that I had a loose
connection somewhere, for example.

Tim

wrote:

This has been discussed here several times.

Blow! I searched with google, but obviously not specifically enough.
Sorry!

Are they Philips CFLs?

Yes, they are. I bought Philips rather than the el-cheapo option
becaus I thought they'd be better designed. That'll learn me!

Basically they are not too well designed
and the capacitance of the live and switch-wire is enough to make
them flicker.

Do I get the impression I might as well just live with it, then? It's
not bothering me, except to make me vaguely worried that I had a loose
connection somewhere, for example.

Tim

If it doesnt bother you its ok as is. If it does, 2 resistors in
series
picked to dissipate a quarter watt fitted in the base of the fitting
would get rid of it.

Philips is one brand I would avoid, the few I've had have been
very poor


NT

Thanks all - I'll fit the new bulb and probably leave it as is.

Tim