This universal triac controller circuit with optocoupler solves the problem that triacs have when functioning at low temperatures (triac needs higher gate
![25A Solid State Voltage Regulator, High power SCR, SSVR [SSVR25A] - $22.50](https://i.pinimg.com/originals/3a/f1/0d/3af10ddc85daced73bdf9a1ce14122e9.jpg)
