hufza:
But what about the level/border to enable the full power, set to 80% in my example code?Will the output ever be 100?
This is still confusing me, please help!
When the PID algorithm calls for more than 80% power the heater will go to 100% power until the demand drops below 80% again.
To make the power more linear you could PWM the heaters like in the original example. For the 0-800W range you would PWM just the 800W heater. For 800-1200W you would PWM the 1200W heater from 66% (800W) to 100% (1200W). For values above 1200 you would keep the 1200W heater full on and PWM the 800W heater from 0% (1200W) to 100% (2000W).