AC Dimming and AC Motor Speed Control How To with Arduino/NodeMCU

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Controlling AC appliances with Arduino always comes with a challenge and when tr requirement is to control the speed of an AC motor or dim an AC light, the challenge is even greater.

In this video, I'm going through the basics of achieving such AC control with the help of a triac and connecting a dimming module to an Arduino or NodeMCU board.

For written instructions, code, and more details be sure to check the Instructable article for the project:

The Arduino library can be found here:

Tools and materials used in the video:

Alternative links on Banggood:

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AC Dimming and AC Motor Speed Control How To with Arduino/NodeMCU
#ACdimming #triac #Arduino #NodeMCU #tastethecode

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[Aisi]

For you who have flickering problem, try to add snubber R-C 100ohm - 10nF across the triacs MT terminal. The triacs available on the market are cheap crap or fake one. BTA16 will couse headache. Try using triacs from old power electronics and its all smooth dimming. Chinese semiconductor sucks...

[MixwellSidechains]

Can I connect more multiple module's zero-crossings pin to the same pin (e.g. pin 2) of the microcontroller or do I have to have a interrupt pin for each as I would the PWM signal pin?

Isn't it the PWM signal pin that controls the triac? Why would I need an interrupt to do so?

[ffwATL]

I was able to implement the same on nrf52832 based on this example. It wasn't as easy as I expected, but using pwm + ppi did the trick. Thank you!

[whyzhr]

Is it necessary to use a universal motor, or is it also safe to use with a solenoid motor?

[razidaufaa]

Excusme sir, I'am sorry, my program encountered an error, =

10 | #include "esp_intr.h"
compilation terminated.

Can you help me sir? Thaks sir

[maestrospavlou]

Hi. what percentage should I send so that I get 220 volts at the output? with 60% the output is 116 volt and if i increase the percentage the output voltage decrease again. can you send your email to contact with you please? thank a lot.

[ocean]

Hi, I am currently working on a project similar to this, this video is very helpful. I do have a question, are the two loads connected in parallel?

[chimpofm]

My dude!! This is what ive been looking for. Can you do a video on how to add pid temp control of the ac fan controler. Outputting the temp value via iot user interface like blynk.

[mrgcav]

Please updaten the Triac Module is no longer on Aliexpress

[TakamiWoodshop]

I like it Bill, I had no idea you could do that with arduino! Playing around with 240v would scare the crap out of me though.

[mrgcav]

In the USA we use 120VAC and I have a large 2.0HP (about 10amps) Inductive AC motor I need to control the the speed of on a table saw. I like you setup. Problem with Triacs is Idle current. So when your circuit is "OFF" how much power is it still drawing ?
If I am Drawing 10 amps then would I not need a much bigger heatsink for the Triac ?
Would you still use an Arduino node MCU if you did this again ?

[mareksendecki]

Im using this module and SUNON DP203A AC FAN and it's acting strange. Bulb works fine but the fan is just buzzing when at 50%. At 70% it works fine but slower than 70% and at 99% it's buzzing and moving at a speed of 1 maybe 2 RPM. Any idea why? I dont have an oscilope to monitor the output wich i suppose may be useful. Thanks for the video :)

[thewaveringwarrior]

Could let us see the code which makes it work with a Potentiometer instead of using the keyboard. I guess you connect the pot to the ADC input pin?

[TheEdevat]

Your content is great! Inspired by this, I started creating a circuit that simulates sunrise and sunset for a chicken farm. I am trying to dim 15 different lamps with a single dimmer module. Everything is fine up to 2 lamps, when there are 3 or more lamps, I constantly get 220v output, dimming does not work. I couldn't understand what I did wrong, can you help me?

[MarkLucas-sx]

Has anyone gotten this sample (SerialMonitorDim) to run on an Arduino Nano? If so what pins did you hook the dimmer module to, and what tweaks were needed to the code? I tried D2 for the Z-C interrupt and D5 (defined as pin 8) for PSM, but no joy. What am I doing wrong? Thanks!

[pwnwnd]

Can we determine the output AC voltage as we want? For example I want the output to be 175V AC

[Funny_sto_rees]

sir what if i only connect live wire to dimmer and the gnd to the load
does it will work fine or not

[yogabharath]

why this lib not work in rp2040 any other alternative src here

[peastfist]

Do you know on how to control 5V fan speed using raspberry Pico ?

[pritambakshi]

Can you metion your Arduino IDE, Esp8266 board manager and RBDDimmer library version.?