Dimmer circuit

The AC light dimmer circuit can control light bulb or speed AC motor, we use triac and SCR as main,and adjust potentiometer and switch,more projects circuits below:

AC Dimmer for Lamp 6.3V

This the circuit AC dimmer low voltage For lamp 6V. While this friends may don’t see the advantage of this circuit. But I thinks first step advantage be something get learn the work of Triac. And have tall safety , because of use AC Low Voltage. Which the work is simple be The UJT Q1 will do the frequency give Triac work or make Lamp the bright. By have work rate of Triac can control with R1 or Be something dimmer there. You will may apply with the size Voltage the other all right. The Q1 use UJT – 2N4891 or other. A friend may gain an advantage from AC Dimmer for Lamp 6V , please sir.

AC Dimmer for Lamp 6.3V

Very cheap ac light dimmer

You may had saw to a complicated AC light dimmer circuit ago. Now let’s look simple, but useful, fairly good.
This circuit uses a capacitor in series with one lamp and accessories with a bit more. Is used to control the light dimmer, Easy and cheap. Power was reduced,without interference, the switch S2 is an option to output size to full size or less.
The value of the capacitor C1 depends on the size and power of the lamp brightness as required. (see table below) may be used several switches, to select the capacity of different time.
Do not use the electrolyte capacitor in this circuit,And if a short circuit could cause the C1 capacitor and should be used polyether or paper types and size at least 300 volts.
Testing should be aware of the charges accumulated by the capacitor.

Very cheap ac light dimmer

AC 100W lights dimmer using a triac

This circuit has can to turn down a light bulb arrives at 100W. If Triac there is tall temperature should hold Heat Sink or let off the heat. The Diac be diode that perform be formed encourage or Trigger Diode 2 kinds are way or Bidirectional. The VR1 use for fine decorate turning down fire. Caution this circuit must is in a box closes all the time that have the electricity flows through.

In figure 2 well than the first circuit
Operation of the circuit be Lamp L1 is adjusted by adjusting the light of VR1. This will serve to control the speed of charging of C1, Because triac will work.
When C1 has charged to the voltage at the triac work.When adjusting the VR1 C1 will charge as little faster lamp is lit.If the adjustment of VR1 C1 will charge very slowly.The little light bulb. Because the triac does not work over the triac during the work.The light bulb will dim down by adjusting VR1.The R1 is placed for protection VR1 prevent damage.The R2, C2 is used to eliminate signal disturbance. Both produced and external circuit.
AC lights dimmer with triac

1200 Watt AC Dimmer by Triac Q4006LT

This is Power AC Dimmer 1200 watt size. It is use a triac Q4006LT. Friends ever tour is the foreign land has and to ever reach rest a hotel. On bed head has will head bed fire decorates. It has a button opens-close and a button controls the brightness with the equipment this/these be AC Dimmer follow our circuit can fine to decorate.

1200 Watt AC Dimmer by Triac Q4006LT

The VR1 for control the light besides when friends apply TRUE work. The Q1 -Q4006LT , should hold heat sink with and should be careful specially prohibit catch one ( part ) which part in the circuit , because read will bump against the electricity can suck. I hopes this circuit , friends can induce apply be AC Dimmer with electric other appliances bump against emphasize kind coil heat equipment , be lucky please yes.

Figure 2 the pcb layout and Components layout of this circuit.

Buy this Here

Note: Fuse you should as current load. for example we use 100Watt lamp we will use fuse current is 100 watt / 220V = 0.45A or 0.5A.

gerson says about: 1200 Watt AC Dimmer by Triac Q4006LT
How can this be a 1200W dimmer when it uses a 0.5A fuse? If anything it should be 5A fuse no?

Sounds more like a 120W dimmer by the maths.

Let’s justified with calculation:

Power (apparent since AC) = VI(rms) = 220Vac x 0.5A = 110VA (max, due to limitation of fuse)

Let’s assume a power factor of 1 (not possible in real life, unless 3 phrase)

Power_in (max) = 110W.
Power_in (let’s said pf=0.7, realistic case) = 110 x 0.7 = 77W, this is more realistic power input.

So if power input is only about 77W, please tell me how it could output 1200W? It’s impossible according to law of conservation of energy. The fuse will just BLOW every time it switches on at full brightness.

To get 1200W input for typical realistic case, you need
fuse rating (Irms) = Pr / (V * pf) =
= 1200 / (220 * 0.7) = 6.5A

Sure you may not need that many current since it is a dimmer, but at maximum brightness you need 6.5A otherwise i’m sure something will blow (the fuse).


  1. el saghir November 24, 2012
  2. prasanth January 13, 2013
  3. jove March 8, 2014
  4. udong November 11, 2014
  5. AZIZ JAMALI September 11, 2015
  6. alex December 16, 2016
  7. michael March 26, 2017

Add a Comment

Your email address will not be published. Required fields are marked *