Given the circuit below:
(I simply plan to switch the light bulb on/off and I will later add an optotriac to the gate.)
As I understand, the circuit should work in this configuration, and the light bulb should glow. But it does not. When I connect the live, it flashes a little, and then nothing, I tried more times, it does the same.
The resistor is working, I measured after every try. The triac in off state shows low resistance between gate and MT1, all other pins are unconnected. If I replace the resistor with a jumper wire, the light bulb glows, but all the current flows through the wire from live to gate and from the gate to MT1. I also tried a snubber circuit between MT1 and MT2 (100n 100R) but nothing changed.
What could be the problem? Is my triac blown? Is this a working design at all?
(I used this as the base of my desing: http://www.instructables.com/id/Small-Triac-Switch/)
Here's an invaluable reference which indicates that your load's on the wrong side of the TRIAC and your gate resistance is way too high.