Temp control

[socalboarder]

Hi all. I've got a question about temp control with heating elements. Within the control box, is it best to turn off and on power to the element or reduce power to hold a specific temp, say 168 degrees?

 

[GrogNerd]

control box would be cycling power to the element to hold temperature, PLUS, though I've only brewed with it once (BoP at LHBS) the Blichmann Tower of Power control box has a power % setting to the element. set high to get to temp or boil, turn down to maintain temp and control boil

High Gravity Brewing control boxes control power through a potentiometer

not sure about other control boxes.

totally my opinion, but I think it would be easier for the control to cycle power than to regulate it.

 

[jeffmeh]

Lots of information on this forum. Learn about PID and PWM.

 

[doug293cz]

Hi all. I've got a question about temp control with heating elements. Within the control box, is it best to turn off and on power to the element or reduce power to hold a specific temp, say 168 degrees?

You can use either on/off or %power to control an element, you can even combine them. If you want to maintain a specific temperature (other than boiling), you need to have a PID, as you will quickly tire of trying to do it by hand, and you will also have severe over/under shoot problems. Whichever way you go for power control, you need to use a solid state switch (SSR or SSVR) rather than a mechanical switch. The required switching rate will cause a mechanical switch to fail pretty quickly.

Brew on

 

[socalboarder]

Other than ease of build, it there any other benefit of an on/off setup to maintain temp? Would it be worth building a variable power output controller?