I've been trying to tinker with an arduino to control the speed of this Chinese fan I bought in Beijing but I cant seem to get the wire correct. the normal is black and red but these have blue, brown and a yellow green swirl. Can anyone help me to find the control wire?
here is the fan reference:
Did it come with a wiring diagram? Or, did you cut the plug off?
Green/Yellow is earth ground.
Brown should be hot
Blue should neutral
In the U.S. where 220 doesn't use neutral, Brown & Blue would both be hot (opposite phase connections).
220v pwm fan or relay module
...to control the speed of this Chinese fan
A relay will provide the required electrical isolation, but it won't allow speed control.
And, PWM doesn't work with AC because of the way TRIACs work. Speed control (or lamp dimming) requires optically isolated TRIAC phase control. It's very similar to PWM except it's synchronized with the AC power line frequency. (That means you need also need an optically isolated AC zero-crossing detector.)
I wanted to control the fan by turning it on low and high with an arduino or fake the pwm action by using a relay to turn it on and off making the fan loose and then gain speed. I couldn’t figure out which wire is a control wire like in most 12v computer fans so I think I may need to go with a relay since I have already blown and arduino from connecting the wrong voltage.
Speed control on those type of motor (induction) is achieved by changing the number of poles, not something you can fiddle with later.Looks like it comes with 3 settings as it is.
Options are, get yourself a different motor e.g. a series low voltage motor or get someone to set up a variable frequency unit to the existing motor on full speed tappings.
The latter will probably see you clear at about Aus$800.00