Hello Everyone.
I was working through a few youtube videos showing how an optocoupler can control a triac to allow a mcu to control high voltage device. When I did the maths I needed to limit the current going through the optocoupler and the gate of the triac to 40ma. After doing all the calcs I ended up needing 5K resistance to make it happen and given the power equation it would have needed to be a few 2W resistors in series.
I took a solid state relay circuit I had from another supplier and it did just that. The only problem is that it had only 2 resistors. Which looked to be 2 W resistors one of 450 ohm and another of 550 ohm. This is far less and my calculations work out to 0.44 amps going to the triac which would probably burn it out. Not to mention that the current will cause the 2W resistors to burn.
The only problem is that the circuit works and works well. I put together a simulation of the circuit using a multimeter to represent the gate current and a switch to represent the triac conducting to provide enough current for the lighr to burn brightly.
I attached the circuit and was hoping that someone could spot the concept this works on because everything I do says it shouldn't work.
I was working through a few youtube videos showing how an optocoupler can control a triac to allow a mcu to control high voltage device. When I did the maths I needed to limit the current going through the optocoupler and the gate of the triac to 40ma. After doing all the calcs I ended up needing 5K resistance to make it happen and given the power equation it would have needed to be a few 2W resistors in series.
I took a solid state relay circuit I had from another supplier and it did just that. The only problem is that it had only 2 resistors. Which looked to be 2 W resistors one of 450 ohm and another of 550 ohm. This is far less and my calculations work out to 0.44 amps going to the triac which would probably burn it out. Not to mention that the current will cause the 2W resistors to burn.
The only problem is that the circuit works and works well. I put together a simulation of the circuit using a multimeter to represent the gate current and a switch to represent the triac conducting to provide enough current for the lighr to burn brightly.
I attached the circuit and was hoping that someone could spot the concept this works on because everything I do says it shouldn't work.