CraftbeerPi Question

[Brian Parfitt]

I tried posting this on the CraftbeerPi thread here, but it seems to be quiet over there. I'm hoping someone here might be able to answer...

I have a question about the CraftBeerPi KettleController. I see you can set the power level of the heater element. I'm wondering how this works. Is the pi just modulating the duty cycle of the heating element to achieve different power levels? Do you have to have the SSR attached to a PWM pin on the Pi i.e. pin 12? Do you simply use the GPIOPWM actor on the PWM pin? I couldn't really find a definitive explanation of how to set this up.

I'd like to be able to ramp my element power up to 100% to bring to boil and then ramp down afterwards to a level sufficient to keep boil rolling

 

[thomashp]

That is definitely how it works. The pi supports hardware PWM on GPIO12, GPIO13, GPIO18, GPIO19. One of these is connected to an ssr to control the duty cycle of the element. The craftbeerpi websiote gives some pretty good diagrams about how it is all wired up. Check it out. CraftBeerPi

 

[Brian Parfitt]

Thanks for the information. I ran a test boil last night and this worked great. 100% power up to a boil and then dialed backed to 50-65% to keep a nice rolling boil. My gosh a 230v/5500 watt element on 6 gallons heats fast. Huge improvement over my old 120V setup. Easily half the time. Can't wait to put this to use during an actual brew!