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General Category => Analog discussion => Topic started by: kourt on December 04, 2009, 20:46:56 PM

Title: Illumination contol
Post by: kourt on December 04, 2009, 20:46:56 PM
I have the follow question for the electronic technicians.
I have one analog signal   0-10 Volts and i want to control ,with this signal, the illumination of one lamp 220Volt ( dimmer ).
So i think that i need one PCB.Any ideas ?
Title: Re: Illumination contol
Post by: kam on December 06, 2009, 14:00:48 PM
This is tricky, as ACV ( that i suppose your 220V lamp is ) cannot be controlled by PWM.

Using a PIC this would be an easy job. A voltage divider by 2 will convert your 0-10volts to 0-5 volts, and the PIC ADC will change this into trigger-angle accordingly. The angle will be proportional to the voltage, but the luminosity of the lamp will NOT be. For this, you need to make the angle change not proportional to the 0-5volts. But that is another matter.

If you do not want to do it without using PIC, you can make a normal RC-driven SCR triggering device, and instead of a potentiometer, use an LDR. The LDR will be inside a light-proof tube with an LED. As DC voltage rises, the LED will light more. As the LED light more, the resistance of the LDR will be decreased. And this will cause the dimmer light to light more and more.
Title: Re: Illumination contol
Post by: kourt on December 08, 2009, 07:25:50 AM
Do you have any drawings without using PIC ?
Title: Re: Illumination contol
Post by: kam on December 08, 2009, 18:06:42 PM
no, not yet...