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Phase control Shaded pole motor

1. I have to control the speed of shaded pole motor. For this i have selected phase control method using TRIAC.
I have a connected a 10K pot at adc input of MCU, as pot is rotated MCU sense the reading & accordingly control the phase. (voltage = 220vac)

2. Now if I connect a 100W bulb at the output & then rotate the pot, I am successfully able to control the intensity of bulb like in gradually goes dimmer or brighter.
Also I have connected a ac voltmeter at load, I can see gradual increase/decrease in voltage of bulb as phase control is done.

3. Problem arises when I connect motor. Attach is the ckt diagram showing snubber circuit & triac connections. Ckt again don't work.

4. I had bought a low cost ceiling fan regulator & strangely it works. I had checked its circuit, the additional feature is it has diac to control firing angle rather than MCU pin for controlling it via opto-triac.
They are using 4q triacs

5. I think my snubber circuit values are wrong?
 

Attachments

  • snubber.pdf
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Replace R2 with 270 ohms and connect it to the anode of the triac instead of from the snubber.

images
 
No, it does'nt require 2 snubbers. The point I'm making is the pin 4 of MOC3021 is to be connected to the "anode" of the triac, not to the snubber.
 
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