I’m looking to control a 230V 3KW heating element.
It will be heating 5-15 liters of water at a time to a specific temperature (~60-70C) and boiling.
The temperature control is fairly easy with thermostat like control since PID is overkill with slow systems like this. However, boiling with 3KW is overkill in a bad way so I want to be able to regulate the power.
I have a few options but I doubt which one is best.
-(1)Simple SSR control. Use time based modulation to “regulate” the power (9 sec on 1 sec off = 90% power etc)
-(2)Zero crossing detection similar to this
-(3)Similar to 2, but switch on on 0 point as well to prevent large current spikes/noise on the AC line.
-(4)Rectify the AC and use ‘simple’ PWM and a thyristor. Probably needs a massive capacitor.
I’m thinking of taking route 3 but perhaps other options are a better choice, I’d love your input.