"john" wrote in message
...

"Brian Sharrock" wrote in message
...

"Kev" wrote in message
oups.com...
Has anybody use the type that fit into a bayonet fitting. I bought a
couple to use when I am on holiday but they don't seem to be very
reliable as they aren't coming on when it turns dark. If I then switch
them off then on they will come on and off again at the preset time but
then won't come on again when it gets dark.

I had one of these some time ago .... IIRC, the unit had to inserted
into the bayonet fitting - preferably during daylight - then the
switch turned ON-OFF-ON rapidly, the lamp illuminated briefly
then was turned 'off' by the ambient daylight. Once daylight
dissapeared the lamp illuminated until dawn the following day.
The lamp remained OFF until dusk time when it came ON, again.

Unfortunately the 'memory' only worked while power remained applied
to the bayonet fitting.

Folks were always switching the damm thing OFF and the programming
sequence needed to be undertaken once more. [ON-OFF-ON]
I got fed up with the palaver and junked the device.


I am now thinking of fitting on the light switch one of those immersion
heater timers.

Kevin


--

Brian


Is the light fitting reflecting too much light back onto the sensor
causing it so switch itself back off.

I dunno .... I was merely addressing the "Has anybody use the type that
fit into a bayonet fitting" part of Kevin's post
However, I'd expect the photo-sensor to be optimised for a more
blue-ish part of the spectrum (daylight) rather than the red-yellow
spectra of filament lamps. [You do the nanometre thingy] .
The device certainly didn't switch itself OFF when the electric light
was flinging photons ... but did switch itself OFF shortly after dawn
and back ON about dusk. It was the fatigue of asking 'Who switched
the light (circuit) OFF then?" and the resulting evasions 'Wasn't me ...
must've been the cat ... " that made me junk it.


--

Brian