Ziegler-Nichols reaction curve recommended control constants

From Zeigler and Nichols

Type of controller Kp Kp/Ki Kd/Kp
P AB - -
P + I 0.9 AB 3.3 L -
P + I + D 1.2 AB 2 L 0.5 L

where A = M / O¥ and B = T / L based on the reaction curve test as illustrated below:

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