12v lamp Dimmer lamp ideas?

stuee

May 7, 2004
183
Joined
May 7, 2004
Messages
183
I have a 12v transformer for interior lights and a few lights for it, but want to make it a dimmer light. the working amps are 250mA.

I would like to know how to wire up these three ways, so i can try each one and see if its any good and use the best....

Touch lamp. touch the metal to turn on dimmest. press again for brighter and again for brighter and again for off.

Manual pot adjuster.

and digital potentimeter. press up to turn up and make brighter and down for darker / off, and a reset button to turn instant off.

Any help and sche... will be helpfull.
Thanks in advance

 

hotwaterwizard2

Jan 8, 2004
2,022
Joined
Jan 8, 2004
Messages
2,022
For the Mechanical one just go to the Junk Yard and get a Dimmer out of any car you like. for the others you can do a couple of things.
Get a standard touch lamp from the store and remove the touch circuit and hook it up to the input of the transformer. or Copy the circuit with Reverse Engineering. Then hook it up to your Transformer plug side.
Here are some circuits if you want to tinker.

12_Volt_Dimmer.gif



dimmer.gif



http://ourworld.compuserve.com/homepages/Bill_Bowden/page6.htm#dimmer.gif


touch.gif



http://ourworld.compuserve.com/homepages/Bill_Bowden/page8.htm#touch.gif

 
Last edited by a moderator:

Kevin Weddle

Feb 23, 2004
1,620
Joined
Feb 23, 2004
Messages
1,620
What you need is to adjust the amount of AC that is applied to the lamp. You can switch power to the lamp if you want and control the duration of the switch. You just assume that there is always a mains voltage present when in fact it depends on the time. To switch the voltage you need a triac that can be biased with a variable pulse width generator. This can be a 555 timer set up to give you a variable pulse width. The variable part is under your control and I believe it is a resistor.

 

audioguru2

Apr 6, 2004
12,026
Joined
Apr 6, 2004
Messages
12,026
Hi Kevin,
How will you syncronize your variable-pulse-width 555 circuit to the mains frequency? The posted LSI IC does it with a built-in phase-locked-loop.

 

trampe

Nov 21, 2004
19
Joined
Nov 21, 2004
Messages
19
have read your problem about a dimmer for interior light.
I have made a complete design about this.
If you are interested, I can mail it to you (as pdf files).
The design can take up to 10 lamps and you can dim one at the time.
It also includes Interface til IR (Infra red).
Best regards.
Terje Olsen :)

 

audioguru2

Apr 6, 2004
12,026
Joined
Apr 6, 2004
Messages
12,026
Hi Terje,
Welcome to our forum.
Don't hide your fantastic design in the mail, please post it here as an attachment to your reply for all of us to see.

 

ante1

Jan 24, 2004
4,138
Joined
Jan 24, 2004
Messages
4,138
Hi Terje,

Det ville vara interesant o se din konstruktjon! ;D

Please post the documents here, PDF files are accepted for posting.

 

trampe

Nov 21, 2004
19
Joined
Nov 21, 2004
Messages
19
Well here it is.
I have send 2 dimmersystem (halogenlight 1 & 2).
It maybe lock rather complicated but it's not.
If any question I will try to explain the circuit.
I have of course the print layout but you have to tell what PCB program you are using
and I will transfer it.
I also have a bigger project about dimmer but this is rather complicated with memory and Eproms ( up to 64 lamps ).
Enjoy!

Regards Terje

 

trampe

Nov 21, 2004
19
Joined
Nov 21, 2004
Messages
19
Once again I will try to send the schematic about the dimmer circuits.
Happy Christmas.

Halogenlight_1.pdf

 

Attachments

  • Halogenlight_1.pdf
    152.7 KB · Views: 16
Top