a$)$ Using the open loop formulae from Ziegler$-$Nichols$$s just for PI$,$ calculate the gain and Tint.

b$)$ Put your values into your controller, put it in AUTO, press VIEW followed by HORIZONTAL GRIS SCALE and select SECONDS, and change the setpoint between $20\%$ and $30\%.$ Capture the screen, so the control can be observed.

Hint: Use minutes, in the formula, as the controller is in mins $/$ rpt$.$ Don$$t worry if your blue pen $($OP$)$ appears somewhat $$triangular$$ in response. This is just due to stiction that has been included in the simulator.