PID Control Tuner

A PID controller is the logic that keeps an automated system on target — holding a room at 78°F, a nutrient tank at pH 6.0, a reservoir at a set level. "PID" stands for its three correction terms: Proportional (react to how far off you are now), Integral (correct for drift that builds up over time), and Derivative (anticipate based on how fast the value is changing). "Tuning" means choosing how strong each of those three reactions should be. This tool applies the classic Ziegler-Nichols method to turn one bump test into a set of starting gains.

When you are commissioning or fixing an automated control loop — HVAC, CO₂ dosing, fertigation pH/EC, irrigation valves — and it hunts, overshoots, or responds sluggishly. This is an engineering/controls task, not an agronomy one; it is crop-agnostic. You first run a test to find Ku and Tu (see the input tips), then this gives you starting gains to load into your controller.

It outputs Proportional Gain (Kp), Integral Gain/Time (Ki/Ti), and Derivative Gain (Kd) for the controller type you picked. Full PID gives the tightest control but can be noisy; PI is a safe, common default for slow processes like temperature; P-only never fully removes the last bit of error. Ziegler-Nichols is a well-known starting point, not a finished tune — it tends to be aggressive, so load these values, watch the loop, and expect to reduce the gains if it overshoots. Enter them into your BMS/controller and observe over a few cycles before trusting them.