Real-time control PLC connected to Simulink is faulty

Hi, everyone

I am trying to build a stepper motor speed control model using simulink with PLC using OPC toolbox. I set Sample Time = 0.01s for all blocks. OPC Read and OPC Write block (Asyn. mode). The PLC Encoder sampling rate is 100ms. I have identified the transfer function as shown in the red circle. The problem with the PID here is that when running a real-time model that only matches (100,110,30), Settling Time = 8s. According to theory, the better set of numbers (16593,31551,4087) is Settling Time = 2s, but when running the real-time model, it is not true when running the simulation. Does anyone know why?