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Eeyore Eeyore is offline
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Default Strange problem with low energy light bulb



Franc Zabkar wrote:

Eeyore put finger to keyboard and composed:
Sjouke Burry wrote:
Eeyore wrote:
Sjouke Burry wrote:

Capacitive leakage from the HOT wire to the switch
wire?

So why doesn't this happen all the time ? Answer, the capacitance is very low,
as is the frequency.

A leak cap has very high impedance, and via
the input rectifier can charge the input cap(slowly).
Then when a threshold is passed, the circuit
produces a flash.
And it only happens, if the input capacity of the
rectifier circuit is low compared to the leak cap.


It flashes every 2 seconds or so.

Clearly a very low leakage current won't do that.



This fellow experimented with a ~1mA leakage current at 240VAC:
http://groups.google.com/group/aus.e...5398c8c?hl=en&

"Changed to 270 kohms and now have a 13W CFL flashing at exactly 1
Hz".


I make that ~ 11nF !

You won't get that easily.

Graham