Does the T3000 PID function allow adjustment of slew-rate?
ie how fast or slow the PID output responds to a sudden change in input.
I cannot see any slew-rate parameter in the PID work screen, so I assume not.
I understand from other posts that the “Time” parameter - minutes or hours provides a way to vary the overall reaction speed.
I put a little table together to help explain PID in the context of our T3000 environment. In my experience with typical HVAC loops it doesnt get more complicated than setting the P term to ’ a few DegC/F’ to commission, then add a little I term to give it some memory. Make sure to set up a trend log for tuning later.
| Parameter | Increase | Decrease |
|---|---|---|
| P | Lazier: Widens the error window; requires a much larger deviation to move the output. | Hyperactive: Narrows the window; a tiny deviation triggers a 100% output jump. |
| I* | Lazier: Heavier memory; averages out sudden spikes; output creeps slowly to setpoint. | Hyperactive: Lighter memory; forgets the past quickly; output races to catch the error. |
| D | Lazier (Heavy Braking): Resists fast movement; slows the output down early to prevent overshooting. | Hyperactive: Removes the brakes; allows the output to move as fast as the sensor changes. |
| Time Interval | Lazier: The controller sleeps longer between calculations; ignores fast-moving noise. | Hyperactive: The controller wakes up constantly; reacts to every minor sensor ripple. |
*Note on Commissioning: Setting I to zero effectively disables the memory/history, leaving you with P-only control. This is the best starting point for the commissioning stage to see the raw Jump of your system before adding the complexity of a ramp