Saving And Reloading Controller Parameters - Siemens SIMATIC Manual

2.1.4

Saving and Reloading Controller Parameters

The schematic below shows the block diagram:
MAN_ON
LOAD_PID
PID_ON
PID_CON
1
0
PI_CON
1
0
Saving Controller Parameters SAVE_PAR
If the current parameter settings are usable, you can save them in a special
structure in the instance DB of FB58 "TCONT_CP" prior to making a manual
change. If you tune the controller, the saved parameters are overwritten by the
values that were valid prior to tuning.
PFAC_SP, GAIN, TI, TD, D_F, CONZ_ON and CONZONE are written to the
PAR_SAVE structure.
Reloading Saved Controller Parameters UNDO_PAR
The last controller parameter settings you saved can be activated for the controller
again using this function (in manual mode only).
Changing Between PI and PID Parameters LOAD_PID (PID_ON)
Following tuning, the PI and PID parameters are stored in the PI_CON and
PID_CON structures. Depending on PID_ON, you can use LOAD_PID in the
manual mode to write the PI or PID parameters to the effective controller
parameters.
PID parameter
PID_ON = TRUE
•
GAIN
•
TI
•
TD
PID Temperature Control
A5E00125039-02
Continuous Temperature Controller FB 58 "TCONT_CP"
&
PFAC_SP,
GAIN,
GAIN,
TI,
TI,
TD,
TD,
D_F,
CONZONE
CONZ_ON,
CONZONE
= PID_CON.GAIN
= PID_CON.TI
= PID_CON.TD
SAVE_PAR
0
PAR_SAVE PAR_SAVE
1
PI parameter
PID_ON = FALSE
•
GAIN
•
TI
MAN_ON
&
UNDO_PAR
PFAC_SP,
GAIN,
0
TI,
TD,
1
D_F,
CONZ_ON,
CONZONE
= PI_CON.GAIN
= PI_CON.TI
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