Hi,
I am from india. I want to control the celing fan speed in my workshop (220V AC voltage) using arduino. can any one provide me with a circuit.
I need to control the speed by sending the data to arduino from my PC.
thankyou in advance
Have a nice day
Ah, I think I know where William is going with this! Something like a normally-on microswitch to cut the power when the arm reaches a limit maybe? :-)
Btw, you might like this site if you've already not seen it. I'm not super-familiar with the site, but it's nice to see the circuit simulated (and animated), so if you click on the link to go to the applet (needs java), then it opens up a new window like below, and if you click on Circuits->Misc Devices->Silicon Controlled Rectifiers->SCR (which for DC is close enough and will work for DC as will a triac) then you'll see a circuit where you can click on the switches to turn them on and off. You could also modify the circuit, since it is a complete simulator, by right-clicking anyhere.
But for low voltage DC control, nothing beats the MOSFET, since it can switch lots of amps, and may be cheaper and smaller than triacs. The only problem is that most are surface-mount, but I remember someone finding some TO-92 packaged ones. I'll see if I can find the name. The discrete mosfets are good for controlling power in one direction, but for two-direction then the circuit does start to get big, so an IC becomes more practical. Recently I used an IC for the control, and used it to switch four external mosfets, using MC33033 (old IC, but still manufactured and quite nice - it's designed for brushless motors, but it can be used with DC motors, shown in figure 45 of the datasheet).
