Parameter Declaration Data type Description
FIL_CYC OUTPUT INT NO OF CYCLES FOR MEAN-VALUE FILTER
n The process variable is averaged over FIL_CYC
cycles. When necessary, FIL_CYC is increased
automatically from 1 to a maximum of 1024.
n Default: 1
n Range of Values: 1 ... 1024
POI_CMAX OUTPUT INT MAX NO OF CYCLES AFTER POINT OF INFLEC-
TION
n This time is used to find a further (in other words
better) point of inflection when measurement noise
is present. The tuning is completed only after this
time.
n Default: 2
POI_CYCL OUTPUT INT NUMBER OF CYCLES AFTER POINT OF INFLEC-
TION
n Default: 0
n The functionality is based on the PID control algorithm with additional functions for
temperature processes. The controller supplies analog manipulated values and pulse-
duration modulated actuating signals. The controller outputs signals to one actuator;
in other words, with one controller, you can either heat or cool but not both.
n FB 58 TCONT_CP can be used either purely for heating or purely for cooling. If you
use the block for cooling, GAIN must be assigned a negative value. This inversion of
the controller means that, for example if the temperature rises, the manipulated vari-
able LMN and with it the cooling effort is increased.
n Apart from the functions in the setpoint and process value branches, the FB imple-
ments a complete PID temperature controller with a continuous and binary manipu-
lated variable output. To improve the control response with temperature processes,
the block includes a control zone and reduction of the P-action if there is a setpoint
step change. The block can set the PI/PID parameters itself using the controller
tuning function.
The values in the controller blocks are only calculated correctly if the
block is called at regular intervals. Therefore, you have to call the con-
troller blocks in a cyclic interrupt OB (OB 30 ... 38) at regular intervals.
The sampling time is predefined on the parameter CYCLE.
The setpoint is entered at input SP_INT in floating-point format as a physical value or per-
centage. The setpoint and process value used to form the error must have the same unit.
Depending on PVPER_ON, the process value can be acquired in the peripheral (I/O) or
floating-point format.
PVPER_ON Process Value Input
TRUE The process value is read in via the analog peripheral I/Os (PIW
xxx) at input PV_PER.
FALSE The process value is acquired in floating-point format at input
PV_IN.
Application
Setpoint Branch
Process Value Options
(PVPER_ON)
VIPA SPEED7
Standard
PID Control > FB 58 - TCONT_CP - Continuous Temperature Control
HB00 | OPL_SP7 | Operation list | en | 18-30 864
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