The PID instruction compares the measured values (process variable) and the set values (set point). The measured values are based on analog input and temperature input. The instruction then adjusts the output values to even the gap between the process variables and the set point. You can combine P control, I control, and D control in PID control. Specify each below mentioned parameter to be controlled.
The output value calculated by the PID control is generally expressed by the following formula.
KP = Proportional Constant
E = Deviation (SP-PV or PV-SP)
Reset = Integral Calculus Time
Rate = Differential Calculus Time
Using the [Tuning] tab that will be described later, adjust the sampling time to reduce the effect of noise on deviation. The following formula shows the result of filtering on the deviation.
EF = Result of filtering on deviation
Tloop = Frequency data
TFilter = Sampling Frequency
E = Deviation (SP-PV or PV-SP)