Creating a large instantaneous jump in set point will cause the integral term to accumulate an extremely large value, resulting in a significant overshoot when the temperature reaches the setpoint. This could be avoided by disabling the integral term during ramp, but as far as I know, there's no method to change PID coefficients on the fly. In can also be alleviated by using the max and min integral parameters in the BCS, but again, these can't be changed on the fly, so changing these could potentially affect performance at steady-state.brahn wrote:I can't say what the purpose was originally, but my understanding of ramp mode is that it's primarily used for fermentation to allow you to ramp the temperature up/down slowly over hours/days.
I would think that when going from step to step in a step mash you would want the error to start out large so you get to the destination temp as quickly as possible. The PID will slow it down as it gets closer to the destination.
Also, it's a very bad idea to reach destination temp "as quickly as possible" when mashing as this could easily denature the enzymes in the mash. I typically run my ramps around 2 degrees/minute.
