Circuit Design Help/Schematics Needed

[Dan Ricketts]

Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both of
these actions to be able to be timer controlled, or triggered when an input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Many thanks

Dan Ricketts

 

[john jardine]

"Dan Ricketts" <Someone@Somewhere.com> wrote in message
newswRjd.441$Eh6.170@newsfe2-gui.ntli.net...

Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both
of
these actions to be able to be timer controlled, or triggered when an
input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use
in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for
my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated
as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge
is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Many thanks

Dan Ricketts

Can't see a need for a timer ,soft start, or incandescents. The ones I've
seen are just a big bank of flourescent tubes (about 10 off 80watt tubes,
c/w anti-glare panel) to sit in front of.
The tube phoshors -must- be a matched 'daylight' colour, having a strong
bluish tinge. A little uncommon but available from specialist sources.
regards
john

 

[Dan Ricketts]

"john jardine" <john@jjdesigns.fsnet.co.uk> wrote in message
news:cmopd9$q7u$1@newsg2.svr.pol.co.uk...

"Dan Ricketts" <Someone@Somewhere.com> wrote in message
newswRjd.441$Eh6.170@newsfe2-gui.ntli.net...
Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset
time
period (say 30 minutes) and also bring the load back up to full power
(i.e
increase voltage from 0% to 100%) over the same time period. I need both
of
these actions to be able to be timer controlled, or triggered when an
input
goes high (e.g. one input for each function). I want to use the circuit
to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use
in
the treatment of SAD (Seasonal Affective Disorder). There are
commercially
designed/built models available - but these are a bit too overpriced for
my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated
as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge
is
only up to GCSE level, but I'm sure I could manage something a little
more
complex if push came to shove!)

Many thanks

Dan Ricketts

Can't see a need for a timer ,soft start, or incandescents. The ones I've
seen are just a big bank of flourescent tubes (about 10 off 80watt tubes,
c/w anti-glare panel) to sit in front of.
The tube phoshors -must- be a matched 'daylight' colour, having a strong
bluish tinge. A little uncommon but available from specialist sources.
regards
john

Hi John,

Thanks for your reply. What you are thinking of are light boxes (that's the
next thing I'm planning to build). The idea behind the dawn/dusk simulator
is that it simulates the rising/setting of the sun, which is supposed to be
particularly helpful in cases of SAD (you wake up to the slow 'rising' of a
light source instead of waking in the dark - which I have to given my job).

Many thanks

Dan

 

[John Larkin]

On Mon, 08 Nov 2004 21:26:45 GMT, "Dan Ricketts"
<Someone@Somewhere.com> wrote:

Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both of
these actions to be able to be timer controlled, or triggered when an input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Many thanks

Dan Ricketts

X10 dimmer module?

John

 

[Robert Monsen]

Dan Ricketts wrote:

Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both of
these actions to be able to be timer controlled, or triggered when an input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Other people have suggested X.10. If you go this way, I'd watch the
maximum power requirements; most of those dimmers are designed for
lamps. I'm guessing your daylight simulation bulb is a halogen, or
something similar. That may require more current than these little
dimmers can take. Also, you probably are going to have to do some
programming yourself to get them to dim over a 30 minute period.

If you know how to program, and you can't get an X.10 dimmer that has a
big enough current capability, you might be able to replace it's triac
with one that can handle more current. However, watch the current
required for triggering, since different triacs have different
requirements, and a circuit designed to trigger one triac may not be
able to trigger another one. Extra heat may also be a concern, although
triacs don't typically have a problem with this, since they trigger fast.

I would personally use a microcontroller to control a big triac.
However, I already have the setup, and know how to program them. If you
don't know this stuff, it'll take time to figure out. The basic stamp is
another way to go that may require less startup time (but which will be
more expensive than a simple microcontroller).

Another option would be some kind of analog timer circuit, controlled by
a ramp voltage. However, an accurate ramp over 30 minutes, while not
impossible, seems kinda hard to me without leakage compensation and
stuff like that. One of the analog geniuses might come up with something
like this for you.

There is also the low-tech solution, which is to buy a dimmer that can
handle the current at the hardware store (if you can find one), and use
some kind of mechanical arrangement, like a clock, to turn it slowly.
Since you'll need to sit in front of the light, starting and stopping it
doesn't have to be automatic. Reversing directions might be a challenge.

--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.

 

[mike]

John Larkin wrote:

On Mon, 08 Nov 2004 21:26:45 GMT, "Dan Ricketts"
Someone@Somewhere.com> wrote:


Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both of
these actions to be able to be timer controlled, or triggered when an input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Many thanks

Dan Ricketts



X10 dimmer module?

John

Check the X10 site for "firecracker" It's a kit with a computer
interface and control module.
Most of the SAD lights I've seen have been fluorescent. Most of 'em
can't be dimmed at all. Most of the X10 stuff won't dim a fluorescent
either. You might have to go with some kind of mechanical variable
shutter or tilting of the whole panel.

FWIW, I went thru the SAD light stuff with a former girlfriend.
SAD is a psychological ailment. She was CONVINCED...make that
ADAMANT... that a $20 homemade light could NOT POSSIBLY work. Had to be
the $800 commercial lamp.
$800 later, she was just as "wacked out" as before. What we won't go
thru for a woman. But I digress...

I'd use a firecracker to dim an incandescent then turn on the SAD light
with an appliance module when it gets to be "sun up". Early morning
light is kinda orange anyway.

Put a big sticker on the front that says,
"Approved by the institute for SAD research".

The sticker will be the most effective part of the treatment.
mike


--
Return address is VALID.
500MHz Tek DSOscilloscope TDS540 $2200
http://nm7u.tripod.com/homepage/te.html
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
http://www.geocities.com/SiliconValley/Monitor/4710/

 

[Rich The Philosophizer]

On Mon, 08 Nov 2004 21:26:45 +0000, Dan Ricketts wrote:

Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both of
these actions to be able to be timer controlled, or triggered when an input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Go to your local Home Improvement store and ask for a sex light. They do
exactly what you say.

Cheers!
Rich

 

[Product developer]

"Dan Ricketts" <Someone@Somewhere.com> wrote in message news:<pwRjd.441$Eh6.170@newsfe2-gui.ntli.net>...

Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both of
these actions to be able to be timer controlled, or triggered when an input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Many thanks

Dan Ricketts

Regardless of the light source you need to maintain the color
temperature of the source to get the benefits of the spectrum. If you
dim a halogen source you will lower its color temperature and spectral
output.

What you are really trying to do is get the body to reduce the
production of Melatonin and increase the production of seratonin
primarily via the optic nerve. Both are triggered by the absence or
presence of full spectrum or at minimum photopic light.

If I were doing this I would go with the Tube type lamps and build a
simple shutter over the lamp housing. Many window blinds can be
operated by a remote control gear reduced DC motor. Put a timer on the
motor and a couple limit switches, viola full color temperature
variable apertured lighting source.

You might wish to take a natural supplement like raw adrenal gland to
aid in energy level which inherently affects mood.

 

[Yves]

"Dan Ricketts" <Someone@Somewhere.com> a écrit dans le message de news:
pwRjd.441$Eh6.170@newsfe2-gui.ntli.net...

Hi all,

I am trying to find a circuit that will allow me to automatically dim an
incandescent load (i.e. reduce voltage from 100% to 0%) over a preset time
period (say 30 minutes) and also bring the load back up to full power (i.e
increase voltage from 0% to 100%) over the same time period. I need both
of
these actions to be able to be timer controlled, or triggered when an
input
goes high (e.g. one input for each function). I want to use the circuit to
run a dawn/dusk simulator (two 240v AC daylight simulation bulbs) for use
in
the treatment of SAD (Seasonal Affective Disorder). There are commercially
designed/built models available - but these are a bit too overpriced for
my
liking.

Any help/suggestions that anyone could offer would be greatly appreciated
as
I've had a google and am unable to find anything of much practical value
(however the only slight problem I have is that my electronics knowledge
is
only up to GCSE level, but I'm sure I could manage something a little more
complex if push came to shove!)

Many thanks

Dan Ricketts

Hi Dan

I've exactly what you need.
It's build around a PIC 16F873 processor.
I could send you schemos and even PCB along with the programmed PIC.
THIS IS NOT A COMMERCIAL OFFER.
Mail me direct.

Yves.