Chapter 6 Applied Instructions 6_ 6-203 Setting Operand Data type Function Description range Tf REAL Derivate-action time constant Range of positive single- precision floating- point numbers (unit: sec) If the derivate-action time constant is less than 0, Tf is 0 and it is not controlled by the derivate-action time constant (derivative smoothing). PID EQ _ BOOL PID formula types TRUE: dependent formula FALSE: independent formula PID DE _ BOOL The calculation of the PID derivative error TRUE: use the variations in the PV to calculate the control value of the derivative (Derivative of the PV). FALSE:
use the variations in the error (E) to calculate the control value of the derivative (derivative of the error). PID DIR _ BOOL PID forward/reverse direction True: reverse action (E=SV-PV) False: forward action (E=PV-SV) ERR DBW _ REAL Range within which the error value is counted as 0. Range of single- precision floating- point numbers The error value (E) is the difference between the SV and the PV. When the setting value is 0, the function disabled; otherwise the CPU module checks whether the present error is less than the absolute value of ERR DBW, and checks _ whether the present error meets the cross