Siemens Simatic S7-1500

Instructions
9.4 PID basic functions
PID control
Function Manual, 03/2017, A5E35300227-AC
453
9.4.1.4
Input parameter CONT_C
Table 9- 13 Input parameter CONT_C
Parameters
Data
type
Default
Description
COM_RST BOOL FALSE The instruction has an initialization routine that is processed when the "Restart"
input is set.
MAN_ON BOOL TRUE If the input "Enable manual mode" is set then the control loop is interrupted. A
manual value is set as the manipulated value.
PVPER_ON BOOL FALSE If the process value is to be read in from the I/Os, the PV_PER input must be inter-
connected with the I/Os and the "Enable process value I/Os" input must be set.
P_SEL BOOL TRUE The PID actions can be switched on and off individually in the PID algorithm. P-
action is on when the "Enable P-action" input is set.
I_SEL BOOL TRUE The PID actions can be switched on and off individually in the PID algorithm. I ac-
tion is on when the input "I-action on" is set.
INT_HOLD BOOL FALSE The output of the integral action can be frozen. For this the input "I-action hold"
must be set.
I_ITL_ON BOOL FALSE The output of the integral action can be set at the I_ITLVAL input. For this the input
"Set I-action" must be set.
D_SEL BOOL FALSE The PID actions can be switched on and off individually in the PID algorithm. D-
action is on when the input "Enable D-action" is set.
CYCLE TIME T#1s The t
ime between block calls must be constant. The "Sampling time" input specifies
the time between block calls.
CYCLE >= 1ms
SP_INT REAL 0.0 The input "Internal setpoint" is used to specify a setpoint.
Permissible are values from -100 to 100 % or a physical variable 1).
PV_IN REAL 0.0 At the "Process value input" you can assign parameters to a commissioning value
or you can interconnect an external process value in floating-point format.
Permissible are values from -100 to 100 % or a physical variable 1).
PV_PER WORD W#16#0000
The process value in I/O format is interconnected with the controller at the "Process
value I/0" input.
MAN REAL 0.0
The "Manual value" input is used to set a manual value using the operator interface
functions.
Permissible are values from -100 to 100 % or a physical variable 2).
GAIN
REAL
2.0
The "Proportional gain" input specifies controller amplification.
TI TIME T#20s The "Integration time" input determines the time response of the integral action.
TI >= CYCLE
TD TIME T#10s The "Derivative action time" input determines the time response of the derivative
action.
TD >= CYCLE
TM_LAG TIME T#2s Time lag of the D-action
The algorithm of the D-action contains a delay for which parameters can be as-
signed at the input "Time lag of the D-action".
TM_LAG >= CYCLE/2
DEADB_W REAL 0.0 A dead band is applied to the system deviation. The "Dead band width" input de-
termines the size of the dead band.
DEADB_W >= 0.0 (%) or a physical variable 1)