Triacs and Outlets (bluetooth and Diac Dimmer)

I'll try english, so dont blame me , help me if it's the case.

Before you try this project read about triacs, diacs, AC requirements and other topics that are used for build the two dimmers, because I wont explain anything about it, so youre in your own and please be careful, dont be a fool.

Let's begin,


The project here contains two devices if you which to call it , both use a triac but the main difference is how it is drive, one is a Dimmer based on a triac with diac, this require a "hand manipulation" to change the intensity or energy that an AC load will receive eg(incandescent lamp or drill motor), dont use this dimmer with any ac load like CLF(fluorescent light) or Tvs ....this one dont need a DC power source it is the easy one, straight forward .

The second do the same job but the variations are controller with an optoTriac, wich is drive by a microcontroller via bluetooth, this one require a dc power source, i used a cheap dangerous chi--se power supply or charger

For this project you will need:


Triac (bt137, bt138) peak one according to your application , this mean voltaje , current and power requirements.

Diac (28 volts is ok)





capacitors(high and low voltages rates)


small Dc power supply or charger (one that allows a input of 110, 220 or according to your need)



conectors for ac line

screw connectors

2 outlet box

Microcontroller(msp430g2553 dont blame me again,I could use other uC
with less features but i was the only one that I have on hands)

.....and everything else you see in the pictures below, (if you know what are the names of the materias that are not listed in English please comment about it, eg. fusible which in english is fuse, so I'll apreciate your input/help )

NOTE: I didn't say the values for certain components of the circuit because there are a bunch of sites that explain what values should be peak up and even more fun how to calculate them.

Step 1: Test Your Circuit

I wasnt planning to publish this, so few photos where taken, this is one of them when I mounted the dimmer based in the diac in the breadboard, after testing I decide to implement the one with the bluetooth directly on the pcb since both circuit have the same principle.

Step 2: Case and Pcb Mesaurements

I remind you that the based on bluetooth is optical isolated from the mains(MOC3021) and galvanic Isolated from the power source(cellphone charger)

I use eagle for the pcb if you need the files just tell me

Step 3: Final Result With the Triac With Diac Dimmer

The circuit works like a charm , I have to glue (sorry) some things to keep it in place without major risk

Step 4: Final Result With Bluetooth

The application was develepoed using MIT appInventor, Sorry for not take a video, not much resources available :D

Any question or suggestion (like 404 english grammar not found) could be leaved in the comments thanks

Step 5: The Results

the original one

version 2.1



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