Mains Dimmers And how (not) to work with mains voltage Tim Clark - PowerPoint PPT Presentation

Introduction Background Approach Waveform Slicing Finally Mains Dimmers And how (not) to work with mains voltage Tim Clark (eclipse) October 17, 2014 Tim Clark (eclipse) Mains Dimmers

Introduction Background Approach Waveform Slicing Finally DMX Previous talk on DMX Now I’ve made the other end A mains dimmer Tim Clark (eclipse) Mains Dimmers

Introduction Background Approach Waveform Slicing Finally Background Approach BIG potentiometer (used to work that way) Instead we slice the waveform TRIAC work for this Tim Clark (eclipse) Mains Dimmers

Introduction Background Approach Waveform Slicing Finally TRIAC TRIACs are (essentially) 2 back to back thyristors Turns on when triggered Turns off only when supply hits 0v (ish) Tim Clark (eclipse) Mains Dimmers

Introduction Background Approach Waveform Slicing Finally Waveform Slicing Mains hits 0v 100 times a seconds (twice a cycle) Detect the 0 cross and time as far as you need Tim Clark (eclipse) Mains Dimmers

Introduction Background Approach Waveform Slicing Finally Waveform Slicing U1 7805 F2 D5 1N4001 R2 330 Ω C1 D3 D4 F1 100 µF 1N4001 1N4001 V1 D6 D1 D2 sine TRI1 1N4001 1N4001 50 Hz TRI2 R1 XFMR1 10 kΩ LAMP1 100 Ω Tim Clark (eclipse) Mains Dimmers

Introduction Background Approach Waveform Slicing Finally The Internet Slides Available at http://sucs.org/~eclipse Tim Clark (eclipse) Mains Dimmers

Introduction Background Approach Waveform Slicing Finally Questions? Any Questions? Tim Clark (eclipse) Mains Dimmers