Hi All,
First post here. I hope I don’t bore everyone.
I have just spent some time designing a small water heater controller and would like some help from those with more experience than I have. Mechanical thermostats have too much dead band and this design should provide very little hysteresis. PID controllers are way too expensive and complicated. So, I gave it a shot. I welcome suggestions, constructive criticism, and sage advice. I am sure I did not get it all right.
I am concerned about the wattage of the resistor on the AC side of the Triac. Any help is appreciated.
I calculated the current through an LED that will show the state of the heater. I shot for 5ma but am not sure I got it right.
I shot for 30ma for the IR LED in the optoisolator. Same question there. Did I get it right?
The Triac is a 12A job that I think should get ‘er done with ease. Maybe a heat sink is necessary?
The schematic is attached. I hope you will give it a look and tell me what you think.
Thanks
Moniker
First post here. I hope I don’t bore everyone.
I have just spent some time designing a small water heater controller and would like some help from those with more experience than I have. Mechanical thermostats have too much dead band and this design should provide very little hysteresis. PID controllers are way too expensive and complicated. So, I gave it a shot. I welcome suggestions, constructive criticism, and sage advice. I am sure I did not get it all right.
I am concerned about the wattage of the resistor on the AC side of the Triac. Any help is appreciated.
I calculated the current through an LED that will show the state of the heater. I shot for 5ma but am not sure I got it right.
I shot for 30ma for the IR LED in the optoisolator. Same question there. Did I get it right?
The Triac is a 12A job that I think should get ‘er done with ease. Maybe a heat sink is necessary?
The schematic is attached. I hope you will give it a look and tell me what you think.
Thanks
Moniker