Do Compact Flouro Lights always periodically flash after switch off?

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View


Just bought some Fairway cool white 20W Compact Fluoro bulbs
from Bunnings and unlike the old ones they replaced they emit a
dull flash every minute or so after they are switched off. Is
this normal?  They 're in the kids bedroom and they didn't
notice this phenomenon with the previous compact fluoros.  The
new ones only cost $14.95 for a pack of 4 made in China
(distributed by Nelson Lamps Australia) so I guess it might be a
matter of you get what you pay for. I guess I will have to
invest in something better so the kids get a decent nights sleep
and don't wake up shell shocked.

--
Regards
Blue

We've slightly trimmed the long signature. Click to see the full one.
Re: Do Compact Flouro Lights always periodically flash after switch off?



Quoted text here. Click to load it

It would be interesting if you try the following test:
If you take it out of the socket after switching it off, does it still
flash, or does it only flash if it is still in the socket?

If it only flashes whilst in the socket then: It could be leakage in the
wiring to the switch providing a few microamps which then charges up the
caps inside the CFL, and when the voltage reaches a certain point, the lamp
tries to start.  If it is this, then a high voltage resistor of a few
megaohms across the CFL might fix it, but I am not sure how this could be
done in a way that meets the wiring rules.  Other option would be to find
and eliminate the leakage in the switch wiring.

If it flashes even out of the socket then a better CFL might be in order.
At the moment I'm in the UK and the Osram 15000 hour ones made in Germany
are only about $4 here and they work very well.

Chris

Re: Do Compact Flouro Lights always periodically flash after switch off?



Quoted text here. Click to load it

Recently in the UK, Morrisons supermarkets had 18W (10%0W) for 99p on buy
one get one free, I bought about £15 worth - they're not going to come up at
that price again for a while! Incidentally I've used a few already and no
problems.



Re: Do Compact Flouro Lights always periodically flash after switch off?


Quoted text here. Click to load it

I've got a couple (also from Bunnings) that do the same thing. It only
happens on the circuits wired for 2-way switching. The switched
conductor runs in a cable with a live conductor. I just put it down to
coupling charging the capacitor to a point that the lamp strikes (as
mentioned in another post).

Of about 25 I've bought, 2 or 3 of these 20W lamps failed early in their
life. One went with a loud bang and took out the breaker. Pressure on
the internal fuse caused a short as the insulation heated and squashed.

Otherwise they've been good. More light and they don't get as hot as the
older Philips CFL's they replaced.

Regards
Paul

Re: Do Compact Flouro Lights always periodically flash after switch off?


They flash out of the sockets and they are not wired for 2 way
switches.

--
Regards
Blue

We've slightly trimmed the long signature. Click to see the full one.
Re: Do Compact Flouro Lights always periodically flash after switch off?


"They flash out of the sockets and they are not wired for 2 way
switches."

...well sometimes. I just removed one as a test and it didn't
flash until the second I tried put it in the socket and it made
contact with the metal fitting.


--
Regards
Blue

We've slightly trimmed the long signature. Click to see the full one.
Re: Do Compact Flouro Lights always periodically flash after switch off?


and that is what happens each time. Take it out and it flashes
the moment you put it back in the socket.

--
Regards
Blue

We've slightly trimmed the long signature. Click to see the full one.
Re: Do Compact Flouro Lights always periodically flash after switch off?


Quoted text here. Click to load it

sounds like there's a low current on the light socket when the switch is off.

easiest fix could be to solder a high resistor between the contacts of the
bulb. Maybe a 3.3M surface-mount type would do it.

Bye.
   Jasen

Re: Do Compact Flouro Lights always periodically flash after switch off?


Quoted text here. Click to load it


I would be interested to see just how much erp is available

Re: Do Compact Flouro Lights always periodically flash after switch off?


you dont have any electronic light switches in line, like remote
controlled light switches (also used in remote fans) or timer switches?
these use a low powered feed through the lamp to complete the circuit,
same with some sensor lights and touch lamps.

electronic lamps arnt too greatful about running in these.

other wise, radio interference like from near by radio and tv
transmitters could be inducting a charge in the cable run. this does
happen in some radio transmitter huts where the amount of rf energy is
enough that fluro lamps no longer switch on and off, its on or dim :)

Re: Do Compact Flouro Lights always periodically flash after switch off?


Re: you don't have any electronic light switches in line, like
remote
controlled light switches (also used in remote fans) or timer
switches? "

No; none of those and it doesn't matter which light socket in
the house I put them in the result is the same.

--
Regards
Blue

We've slightly trimmed the long signature. Click to see the full one.
Re: Do Compact Flouro Lights always periodically flash after switch off?


I've sent Nelson Lamps Australia an email asking about this
phenomena; I'll let you know if they reply.

--
Regards
Blue

We've slightly trimmed the long signature. Click to see the full one.
Re: Do Compact Flouro Lights always periodically flash after switch off?


The response from the distributor in parts said: "I have checked
out your situation and can confirm that this rarely occurs we
have found after much research that certain homes that are wired
in a way where they are switching the neutral that this may
occur with these lamps."

--
Regards
Blue

We've slightly trimmed the long signature. Click to see the full one.

Site Timeline