Danfoss VLT FC 100 Series Programming Manual page 166

3. Parameter Description
[2] Slow Pressure
[3] Fast Temperature
[4] Slow Temperature
21-01 PID Performance
Option:
3
* Normal
[0]
[1] Fast
21-02 PID Output Change
Range:
*
0.10 [0.01 - 0.50]
21-03 Minimum Feedback Level
Range:
-999999.999 User Units
[-999999.999 - Value of par. 21-04]
21-04 Maximum Feedback Level
Range:
999999.999 User Units
par. 21-03 - 999999.999]
21-09 PID autotuning
Option:
*
Disabled
[0]
[1] Enabled Ext CL 1 PID
[2] Enabled Ext CL 2 PID
[3] Enabled Ext CL 3 PID
3.19.3. 21-1* Closed Loop 1 Ref/Feedback
Configure Extended Closed Loop 1 Controller reference and feedback.
166
Function:
Normal setting of this parameter will be suitable for pressure control in fan systems.
Fast setting would generally be used in pumping systems, where a faster control response is desirable.
Function:
This parameter sets the magnitude of step change during autotuning. The value is a percentage of full operating
range. I.e. if maximum analog output voltage is set to 10 V, 0.10 is 10% of 10 V, which is 1 V. This parameter
should be set to a value resulting in feedback changes of between 10% and 20% for best tuning accuracy.
Function:
* The minimum allowable feedback level should be entered here in User Units as defined in par 21-10 for EXT CL
1, par 21-30 for EXT CL 2 or par 21-50 for EXT CL 3. If the level falls below par 21-03, PID autotuning is aborted
and an error message will appear on the LCP.
Function:
* The maximum allowable feedback level should be entered here in User units as defined in par 21-10 for EXT CL
[Value of
1, par 21-30 for EXT CL 2 or par 21-50 for EXT CL 3 If the level rises above par 21-04, PID autotuning is aborted
and an error message will appear on the LCP.
Function:
This parameter enables selection of the Extended PID controller to be Auto-tuned and starts the PID autotuning
for that controller. Once the autotuning has successfully completed and the settings have been accepted or
rejected by the user, by pressing [OK] or [Cancel] buttons on the LCP at the end of tuning, this parameter is
reset to [0] Disabled.
MG.11.C5.02 - VLT
®
VLT HVAC Drive Programming Guide
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