120v AC Powered Daylight sensor

[lexxtank]

I am trying to make a circuit to control the Christmas lights on the house based on the amount of daylight. Obviously as it gets darker, the lights turn on, and when it gets brighter they turn off. I am very new to electronics, and I can't read circuit diagrams yet. How can I go about doing this? (It needs to accept 120v AC in, and put out 120v AC so I can plug the lights into it directly) Thanks.

 

[Andy1845c]

Don't they make ready made controllers like this?

You won't be able to run the control off 120vac. You will need a source of low voltage DC that controls a relay or triac to switch the 120V lights.

Google "dark detecting circuit" and you will get an idea of the basics of how this is done.

Evil Mad Scientist Laboratories - A dark detecting circuit for your jack-o'-lantern

This one turns on 2 yellow LEDS, but an Opto-isolator could go in there place. The Low voltage circuit should be isolated for safty.

A simple circuit like this will "chatter" on and off when the light level is around the threshold of on/off.

Since you admit you have no experiance, I would work with some low voltage projects and increase your knowledge before you work with AC mains.

 

[Willbe]

A simple circuit like this will "chatter" on and off when the light level is around the threshold of on/off.

Some have a second photocell that uses the light that has just turned on to give the thing some hysteresis.

BTW, if you want a huge "Christmas oscillator" have the controlled lights shine on the sensor.

 

[KMoffett]

Don't they make ready made controllers like this?

What?! I've been using one like this for years. **broken link removed**. Check your local hardware store...I avoid the big box stores to support my local businesses...but you may not.

Ken

 

[lexxtank]

Thank you for all of your replies. I have actually decided to stick with my old timer, but I would like to make the lights dance in some pattern. The point of doing it myself was to avoid saying I just bought something to do it for me. I'd really like to put together my own dancing lights system. Despite being new, have worked with high voltages before without issue. BTW KMoffett, I too try to avoid te big retail chains now. Local businesses care about the customer more than the profit.

 

[Andy1845c]

Are your lights LED or incandescent? LED lights are fun to play with. Theres not much you can do with a string of old incandescents, except make the whole string blink on and off.

Me and my wife bought some LED icicle lights last year. The leds are wired antiparallel in sections of four or five icicle strings. I used a opto-isolated soild state relay and a 555 timer that I could adjust the frequency on to make them twinkle. By adjusting the 555 against the ac line freq. i could make them flicker, twinkle or slowly alternate flash the sections.

 

[lexxtank]

They are the "good old fashioned Griswold family Christmas" C9 Christmas lights. I'm just trying to make different sections of the house blink in a sequence. I'm investigating trying this: **broken link removed** but that device is expensive.