Steve Kraus wrote:
Is there a photoelectric light control such as you might use for outdoor
lighting that cleanly turns power on and off. I have one that seems to use
some sort of triac circuit like a light dimmer. It turns on and off
gradually. If you put your finger over the photocell in daylight you can
make the light come on to varying degrees of brightness by varying the
daylight on the cell. The sort of weird waveform this sort of phase
control puts out is unsuitable for most compact fluorescent bulbs. So I
need to get one that has a pure on/off output.

I was thinking of adding a relay between the control and the light socket.
That would make the switching clean but there's always the possibility that
it will chatter on and off at dusk or dawn. So another possibility is to
use a junk AC adaptor with a DC output switching a relay with a low voltage
coil. A capacitor on it would iron out any chatter.

But presumably there's already something available that is suitable.

Steve,

The type of photo control you need is available. I was in the same
situation installing CFL fixtures outside the last two houses I've
owned. What you need to do is look at the controls themselves,
which may require opening the package in the store, to read the
"fine print" specs on the controller itself. What you're looking
for is wattage/current ratings listed for both incandescent and
Ballast loads. If it has a Ballast rating, it's suitable for switching
fixtures with ballasts, such as flourescent, sodium, mercury vapor,
etc. These controllers have relays in them. You can hear it click
when it turns on or off.

The ones I've used were made by Area Lighting Research, but the
outside package/box could have various brand names, but the
controllers themselves have the ALR brand. I got mine at the
large home-improvement warehouse type stores, so it shouldn't
be hard to find. They are a bit larger and cost a couple bucks
more than the triac-type "incandescent only" ones but will work
with any kind of load within its current/wattage limits.

Mike
WB2ME