A project log for Simple Universal Motor Speed Controller

The goal of this project is to build a simple universal motor PID speed controller using a minimum number of components

rhysRhys 06/13/2014 at 13:470 Comments

Well, good thing first one was just a prototype.  I seem to be having an issue with actually firing the triac.  Still troubleshooting at this point, but I may end up having to either add a proper opto circuit to fire the triac, or switch to a random fire SSR (looking at cost differences before I decide).  While all the data I can find says I SHOULD be able to fire this particular gate sensitive triac directly from an MCU pin, I can't seem to actually get it to fire.  I can see the trigger signal and zero cross signal timing on my logic probe, but the triac does not appear to be latching on.  I've tried adjusting the timing, I've tried adjusting the trigger pulse width (up to about 200us), nothing seems to work.  Tried manually triggering the triac with 5V and 9V and still nothing.  Not sure what the issue is.  I will update again after I investigate some more.....