triac based dimmer

Triac based Four Step Touch Dimmer:

Triac based Four Step Touch Dimmer S.VIJAY PRESENTED BY B.SANTHOSHINI E.C.E BRANCH

Overview:

Overview Introduction How it works Block diagram of Triac based Four Step Touch Dimmer Mechanism of Triac &Diac based Four Step Touch Dimmer Working procedure Features of Triac power control based Four Step Touch Dimmer Advantages Applications Conclusion

How it works? . :

How it works? . Initially, when mains switch is ‘on,’ the bulb is ‘off’. Now, if you touch the touch plate, the bulb glows dimly. On second touch, the bulb gives medium light. At the third touch, the bulb is driven fully. Another touch puts off the light

Block diagram:

Block diagram Capacitor Array Transformer less DC Power Supply 6.8V Regulated zener circuit TT6061A Triac 230V Lamp Touch Plate

Working Procedure:

Working Procedure Touch plate is coupled to the touch detector through 820pF, 2kV capacitors C1, C2, and C3 connected in series. Internally IC TT6061A’s touch signal is connected to the counter/decoder via a resistor and clock input CK is connected to the counter/decoder via a frequency generator. Line frequency signal is taken through R4 at pin 2 of IC TT6061A. At zero crossing, the tri ac (BT136) triggers to drive a200W bulb The 6.8V power supply is taken directly from mains through resistors R1 and R3, diode D3, capacitor C4, and zener diode and fed to power-input pin 3 of the IC.

Slide 7:

Pin Assignments of IC TT6061A Pin no. Pin name Function description 1 CK System clock input 2 FI 50Hzlinefrequency 3 VDD Power input pin for VDD 4 TI Touch input 5 CI Sensor control input 6 NC Not connected 7 VSS Power input for VSS 8 AT Angle Trigger Output

Triac Lamp Dimmer Circuit. :

Triac Lamp Dimmer Circuit.

Touch:

Touch Touching this touch dimmer you can increase the light intensity of incandescent lamps in three steps. The touch dimmer is built around 8-pin CMOS ICTT8486A/TT6061A specifically manufactured for touch dimmer applications.

Triac Applications:

Triac Applications

Triac power controll:

Triac power controll A triac control circuit is shown in figure. Here it is controlling ac power to load by switching on and off during the positive and negative half cycles of the input sinusoidal signal. During the positive half cycle of the input voltage, diode D1 is forward biased, D2 is reverse-biased, and the gate terminal is positive with respect to A1 During the negative half cycle, the diode D2 is forward biased and diode D1 is reverse-biased, so that the gate becomes positive with respect to terminal A2- The point of commencement of conduction is controlled by adjusting the resistance R2 .

Applications:

Applications Industrial machinery Agriculture Motors Water pumps

Household applications:

Household applications Ovens Refrigerator AC

Advantages:

Advantages Highly Accurate Low cost and reliable circuit Adjustable Time can be set using potentiometer Four different fixed time schedules Can handle heavy loads up to 7A

Conclusion:

Conclusion By simply touching this touch dimmer you can increase the light intensity of incandescent lamps

Reference:

Reference http://www.circuitstoday.com/triac-applications http://www.circuitstoday.com/diac-applications http://www.google.com

THANK YOU:

THANK YOU