How to control AC 220V fan speed with arduino's PWM output..??

[Joy]

I am able to control the brightness of an LED with a pot and the output via PWM pin..

In the similar way how do I control the speed of a AC 220v fan or light ..??

There should me no humming in the fan

[Nishant_Sood]

In the similar way how do I control the speed of a AC 220v fan or light ..??

That cannot happen with AC light dimming you have to slice at the right time depending on the frequency and voltage to lower the voltage so as to dim, PWM;s won;t work with AC lighting.

[Joy]

yes I know that it is not possible directly..

So what other parts should I use to do That..

Like in this schematic here


How do I control the R1 with arduino...??

[Nishant_Sood]

yes I know that it is not possible directly..

It's not the question of directly or indirectly it's basically because you need to ascertain the Zero Crossing and as per that you have to open the traic for that time only that will give you desired dimming.

[Techone]

@NI$HANT

You forgot to tell Joy your tread. 

@Joy

Check this tread. http://arduino.cc/forum/index.php/topic,91274.0.html

I did a schematic and a code to control AC using an Arduino. It is just for a 12 V AC for now ( I am working on it for the 120 V AV version )

[Nishant_Sood]

You forgot to tell Joy your tread. 

First wanted him to learn that why we are telling him what we are telling him?, just wanted to make him work his way out of that previous concept of PWM'ing the A/C line's.

[Joy]

then how do those remote for home lights and fans control the fan speed...??

[Nishant_Sood]

Go to the link above provided, also learn of zero crossing , google it and then learn how to slice the voltage by using it.

[Joy]

Just found this schematic


it is using an opto coupler and a opto triac driver..

But theoretically how is it controlling the fan speed...??
by switching on and of the fan a number of times and varying that time..??

[Techone]

First, you need to know how a dimmer switch work so you can understand the principle how to control an AC voltage.

Here a link : http://home.howstuffworks.com/dimmer-switch.htm

And go to NI$HANT tread. My design use this principle. Bear in mind it is only one device being control. To control multitude devices is no so easy for me at this time. It is going to be "tricky". It is the sychronization is going to be "tricky" part to control different AC devices at differents "dim" levels.

[mexomagno]

Thanks for the howstuffworks link! This explains it all!

[Nishant_Sood]

Ya but then it helps!

[mattsven471]

Microchip´s Application Notes could help you

[kathait]

 hi nishant joy n everyone  arduino is kind of new to me      i know just a little bit about it.  i want to control my.   ac fan.  ohhh i live in India 220 volt 50 hz
i want to control its speed.        i have  seen  n read all the posts but i havent  understood any of it. plz plz tell me what hardware  and.  what hardware device i have to learn about.    plz   nishant help me.   any adive would be highly appriciated. ✌✌✌✌✌✌

[MarkT]

The simple advice is you can't.  Standard induction motors in domestic appliances cannot
safely be speed-controlled (some can be a little, but its not easy to find out by how much). 
Get a DC fan.