Parameter Status_H - Siemens SIMATIC S7-1200 Function Manual

Instructions
9.4 PID basic functions
9.4.4.9

Parameter STATUS_H

STATUS_H
0
10000
2xxxx
2xx2x
2x1xx
2x3xx
21xxx
22xxx
3xxxx
30002
30005
Note
If you cancel tuning in phase 1 or 2, STATUS_H = 0 is set. However, STATUS_D still
displays the status of the last controller calculation.
The higher the value of STATUS_D, the higher the order of the control process, the greater
the TU/TA ratio and the gentler the controller parameters will be.
See also
Operating principle of the pulse generator (Page 481)
Block diagram TCONT_CP (Page 484)
494
Description
Default, or no/no new controller
parameters
Tuning completed + suitable control-
ler parameters found
Tuning completed + controller pa-
rameters uncertain
Point of inflection not reached (only
if excited via setpoint step-change)
Estimation error (TU < 3*CYCLE)
Estimation error TU too high
Estimation error N_PTN < 1
Estimation error N_PTN > 10
Tuning canceled in phase 1 owing to
faulty parameter assignment:
Effective manipulated value differen-
tial < 5%
The sampling times CYCLE and
CYCLE_P differ by more than 5% of
the measured values.
Remedy
If the controller oscillates, weaken the control-
ler parameters, or repeat the test with a smaller
manipulated value difference TUN_DLMN.
Reduce CYCLE and repeat attempt.
Special case for PT1-only process: Do not
repeat test, if necessary reduce controller pa-
rameters.
Repeat test under better conditions.
Repeat test under better conditions.
Repeat test under better conditions.
Correct manipulated value differential
TUN_DLMN.
Compare CYCLE and CYCLE_P with the cycle
time of the cyclic interrupt priority class and
note any loop scheduler.
Check CPU load. An excessively loaded CPU
can result in prolonged sampling times that are
inconsistent with CYCLE or CYCLE_P.
Function Manual, 03/2017, A5E35300227-AC
PID control