fluorescent low energy bulb flashing when"off"

[bigegg]

@gaz1 mentioned something about this in the "workshop build" thread.

exmrsegg lives in a new build disabled adapted house owned by the local housing federation.
the house was built "on the cheap"

she has a single bayonet socket pendant in the centre of her LR ceiling which is 2W switched.
the bulb (I know it's a "lamp") is a low energy fluorescent:



something like this - not this exact one.

when the switches are "off" the lamp "flashes" about once a minute - but randomly, not at an exact interval.

in the aforementioned thread, Gaz said something about "switched neutral"(?) causing this?

is it a major fault? which wouldnt surprise me, the central heating was a complete botch job.
or just a faulty bulb?

 

[brightspark]

could be a faulty bulb or could be reversed polarity on wiring or just a bit of residual current kicking around specially on a 2 way switch. try another bulb 1st

 

[Dee J]

Capacitive coupling in the wiring to the switch. Generally more of a problem with long switch runs or 2-way switching. Absolutely standard phenomenon. Not indicative of any fault situation. Some lamps are more susceptible than others.

 

[bigegg]

thanks.

 

[brightspark]

stick a filament bulb in job solved

 

[bigegg]

she's going hive>Alexa>led then she doesn't have to get up to turn light off to watch tv

 

[gaz1]

i was aware of this while looking

https://diy.stackexchange.com/questions/11798/why-energy-saving-bulb-flashes-when-the-switch-is-off