Arduino Forum

Forum 2005-2010 (read only) => Hardware => Interfacing => Topic started by: stinky on Jun 12, 2006, 12:04 am

Title: Dimming an AC light
Post by: stinky on Jun 12, 2006, 12:04 am
I want to have dimming control of two AC lamps from arduino.

I've been investigating my options but I'm not sure what is best.

Option 1: Get a DMX dimmer unit and control with the DMX control unit code in the tutorials.

Option 2: Replace the potentiometer in a standard light socket dimmer with a light dependent resistor and control with an LED connected to arduino.

Option 3: Use a light dimmer kit which accepts a 0 - 10V DC analogue control signal. (but how do I create the control signal using the arduino board??)

Can anybody advice which option would be best / easiest?? Is there another option I should try instead??

Thank you!!
Title: Re: Dimming an AC light
Post by: mellis on Jun 12, 2006, 12:45 am
Not sure which option is best, but for #2 you might try a digital potentiometer like a DS1666 (if it's powerful enough for the dimmer).
Title: Re: Dimming an AC light
Post by: admin on Jun 12, 2006, 09:43 am
hello jon

there is a quick way if you're using purely incandescent lights. buy a  velleman K8064 dimmer kit. it should cost around 20 pounds.
this is a voltage controlled dimmer. it can be tuned to work from the 0 to 5 v output of the arduino board. remember to place a big capacitor at the arduino output pin because the dimmer doesn't like the fast PWM pulses.

if you want to drive an analogue dimmer using a 0-10v input you just need to build a simple circuit using an op-amp.
what you need is a non-inverting amplifier with a fixed gain of 2. power the opamp at 12v and you'll get a 0-5v coming from arduino into 0-10v needed by the dimmer.

the above mentioned circuit is just made with an LM358 and 2 resistors....


don't hack esisting dimmers... it's way to dangerous to play with 220V. expecially because cheap dimmers have 220v running allover the circuit and they will happily send it back to the arduino while the velleman dimmer uses an optocoupler to separate the board from the 220V part of the circuit

finally DMX is best used when controlling multiple lights in a big installation. DMX fixtures are not so cheap..

have fun

massimo
Title: Re: Dimming an AC light
Post by: stinky on Jun 12, 2006, 09:14 pm
Oh Massimo! I love you're brain! Give it to me!!!!

(thanks)
Title: Re: Dimming an AC light
Post by: solstiss24 on Mar 06, 2008, 11:33 am
hi,

when using velleman K8064 dimmer kit, is there a need of a SSR between the arduino and the dimmer kit?

does anyone has any references on the code?


thanks in advance...
Title: Re: Dimming an AC light
Post by: mlehmann on Nov 28, 2008, 09:52 pm
remember to place a big capacitor at the arduino output pin because the dimmer doesn't like the fast PWM pulses.

What kind of value are we talking about for the capacitor?
Title: Re: Dimming an AC light
Post by: fubbi on Dec 04, 2008, 02:58 pm
Quote
remember to place a big capacitor at the arduino output pin because the dimmer doesn't like the fast PWM pulses.

What kind of value are we talking about for the capacitor?


I am building a velleman dimmer controlled by a parallax ping. I am just about to connect them, I would really like to know this too before I hook it up.

fubbi
Title: Re: Dimming an AC light
Post by: Grumpy_Mike on Dec 04, 2008, 04:02 pm
About 4.7uF through a 100R resistor.
Title: Re: Dimming an AC light
Post by: azi on Mar 17, 2009, 12:56 pm
you can use transmiters, to flash with those bulbs, 5V closes the circuit
they are cheap, and if you need only 3 bulbs, you don't need to worry about current supply, I could connect 15 of them, the rest is just to program it how you want to work...

http://www.laro.com.pl/pdf/hm4100f-5v.pdf
Title: Re: Dimming an AC light
Post by: satanasmachete on Jan 20, 2010, 01:11 am
Hey here in Mexico we use 110v for our devices, so is there an alternative for the velleman K8064 dimmer kit? or can it be setup to work with 110v instead of 220v??

Thanks in advance!
Title: Re: Dimming an AC light
Post by: Osgeld on Jan 20, 2010, 01:27 am
it will work
Quote
operating voltage: 110-125V or 230-240V AC (50/60Hz)


http://www.vellemanusa.com/us/enu/product/view/?id=521945
Title: Re: Dimming an AC light
Post by: satanasmachete on Jan 20, 2010, 02:11 pm
Thanks!