Chapter 10 Built-in PID Functions
10 - 15
(4) _PIDn_T_i (PID integral Time gain)
- Setting Area
K DEVICE AREA : K1028+32n
Unit : REAL [ -3.4038 ~ -1.17549435e-38 , 0 , 1.17549435e-38 ~ 3.4038 ]
This sets the integral time constant (T_i) of the corresponding loop. As T_i divides the I (integral) term, the
larger T_i, the smaller the integral effect.
If _PIDn_T_i is set to 0, I control is not performed. For more details, refer to 10.6.
T_i can be set in the short/long real number (REAL) range.
(5) _PIDn_T_d (PID derivative Time gain)
- Setting Area
K DEVICE AREA : K1030+32n
Unit : REAL [ -3.4038 ~ -1.17549435e-38 , 0 , 1.17549435e-38 ~ 3.4038 ]
This sets the derivative time constant (T_d) of the corresponding loop. As T_d is multiplied into the D
(derivative) term, the larger T_d, the larger the derivative effect.
If _PIDn_T_d is set to 0, D control is not performed. For more details, refer to 10.6.
T_d can be set in the short/long real number (REAL) range.
(6) _PIDn_dPV_max(PID delta PV MAXimum limit)
- Setting Area
K DEVICE AREA : K1032+32n
Unit : WORD [ 0 ~ 65535 ]
This limits the PV variation of the corresponding loop.
In actual control, PV does not always reflect the exact system state. Unwanted signals caused by sensor
malfunction, noise or disturbance can be mixed and reflected in PV. Like this, PV often undergoes a
sudden change and causes a large change in PID output. It is a priority to prevent a PV change greater
than the value set in _PIDn_dPV_max. Meanwhile, if _PIDn_dPV_max is set too small, the system change
is slowly reflected and the convergence time takes longer. Therefore, setting should be made according to
the system features.
If this is set to 0, the function does not operate.
(7) _PIDn_dMV_max (PID delta MV MAXimum limit)
- Setting Area
K DEVICE AREA : K1033+32n
Unit : WORD [ 0 ~ 65535 ]
This limits the MV variation of the corresponding loop. A sudden change in the output of the control system
may cause a system instability or impose a heavy load on the driver resulting in failure or unstable
operation. To prevent this, this item limits the controller output variation. If this is set to 0, the function does
not operate.
