Determining PID controller constants is described using two of the most commonly used methods. The Ziegler-Nichols open loop and Cohen-Coon methods are demonstrated using Flownex. The system is modeled in Flownex and a system step response is generated. The data from this response is sent to a report where the control constants are calculated. These constants are then tested using a PID controller from the control systems library in Flownex.