Siemens 440 - Manual (Page 238)

Parameter Description Issue 01/06
MICROMASTER 440 Parameter List
238 6SE6400-5BB00-0BP0
P2292 PID output lower limit Min: -200.00
CStat: CUT Datatype: Float Unit: % Def: 0.00
P-Group: TECH Active: Immediately QuickComm.: No Max: 200.00
Sets lower limit for the PID controller output in [%].
Dependency:
A negative value allows bipolar operation of PID controller.
Note:
P2292 = 100 % corresponds to 4000 hex
P2293 Ramp-up /-down time of PID limit Min: 0.00
CStat: CUT Datatype: Float Unit: s Def: 1.00
P-Group: TECH Active: Immediately QuickComm.: No Max: 100.00
Sets maximum ramp rate on output of PID.
When PI is enabled, the output limits are ramped up from 0 to the limits set in P2291 (PID output upper
limit) and P2292 (PID output lower limit). Limits prevent large step changes appearing on the output of the
PID when the inverter is started. Once the limits have been reached, the PID controller output is
instantaneous.
These ramp times are used whenever a RUN command is issued.
Note:
If an OFF1 or OFF 3 are issued, the inverter output frequency ramps down as set in P1121 (ramp-down
time) or P1135 (OFF3 ramp-down time).
r2294 CO: Act. PID output Min: -
Datatype: Float Unit: % Def: -
P-Group: TECH Max: -
Displays PID output in [%]
Note:
r2294 = 100 % corresponds to 4000 hex
P2295 Gain applied to PID output Min: -100.00
CStat: CUT Datatype: Float Unit: - Def: 100.00
P-Group: TECH Active: Immediately QuickComm.: No Max: 100.00
Allows the user to scale the PID output as a percentage value [%].
A gain of 100.0 % means that output signal has not changed from its default value.
P2350 PID autotune enable Min: 0
CStat: CUT Datatype: U16 Unit: - Def: 0
P-Group: TECH Active: Immediately QuickComm.: No Max: 4
Enables autotune function of PID controller.
Possible Settings:
0 PID autotuning disabled
1 PID autotuning via Ziegler Nichols (ZN) standard
2 PID autotuning as 1 plus some overshoot (O/S)
3 PID autotuning as 2 little or no overshoot (O/S)
4 PID autotuning PI only, quarter damped response
Dependency:
Active when PID loop is enabled (see P2200).
Note:
P2350 = 1
This is the standard Ziegler Nichols (ZN) tuning which should be a quarter damped response to a step.
P2350 = 2
This tuning will give some overshoot (O/S) but should be faster than option 1
P2350 = 3
This tuning should give little or no overshoot but will not be as fast as option 2.
P2350 = 4
This tuning only changes values of P and I and should be a quarter damped response.
The option to be selected depends on the application but braodly speaking option 1 will give an all round
good respsonse, whereas if a faster response is desired option 2 should be selected. If no overshoot is
desired then option 3 is the choice. For cases where no D term is wanted then option 4 can be selected.
The tuning procedure is the same for all options. It is just the calculation of P,I and D values that is different.
After autotune this parameter is set to zero (autotune completed).
Level
2
Level
3
Level
2
Level
3
Level
2