Danfoss VLT AQUA Drive FC 202 Programming Manual

Also see for VLT AQUA Drive FC 202: Service guide Installation guide Installation guide Operating guide Installation guide

Contents

3.18 Parameters 21-** Extended ClosedLoopThe FC 202 offers 3 extended closed-loop PID controllers inaddition to the PID controller. These controllers can beconfigured independently to control either externalactuators (valves, dampers, and so on) or be used togetherwith the internal PID controller to improve the dynamicresponses to setpoint changes or load disturbances.The extended closed-loop PID controllers may be intercon-nected or connected to the PID closed-loop controller toform a dual loop configuration.To control a modulating device (for example, a valvemotor), this device must be a positioning servo motor withbuilt-in electronics accepting either a 0–10 V (signal fromVLT® Analog I/O Option MCB 109) or a 0/4–20 mA controlsignal.The output function can be programmed in the followingparameters:• Control card, terminal 42: Parameter 6-50 Terminal42 Output (options [113]...[115] or [149]...[151], Ext.Closed Loop 1/2/3.• VLT® General purpose I/O card MCB 101, terminalX30/8: Parameter 6-60 Terminal X30/8 Output,(setting [113]...[115] or [149]...[151], Ext. ClosedLoop 1/2/3.• VLT® Analog I/O Option MCB 109, terminalX42/7...11: Parameter 26-40 Terminal X42/7 Output,parameter 26-50 Terminal X42/9 Output,parameter 26-60 Terminal X42/11 Output (options[113]...[115], Ext. Closed Loop 1/2/3).VLT® General purpose I/O card MCB 109 and VLT® analogI/O option MCB 109 are optional.3.18.1 21-0* Extended CL AutotuningThe extended closed-loop PID controllers can each beauto-tuned, simplifying and saving time during commis-sioning, while ensuring accurate PID control adjustment.To use PID auto-tuning, configure the relevant extendedPID controller for the application.Use a graphical LCP to react on messages during the auto-tuning sequence.Enabling auto-tuning, parameter 21-09 PID Auto Tuning putsthe relevant PID controller into PID auto-tuning mode. TheLCP then provides on-screen instructions.PID auto-tuning introduces step changes and thenmonitors the feedback. Based on the feedback response,the following required values are calculated:• PID proportional gain.- Parameter 21-21 Ext. 1 Proportional Gainfor EXT CL 1.- Parameter 21-41 Ext. 2 Proportional Gainfor EXT CL 2.- Parameter 21-61 Ext. 3 Proportional Gainfor EXT CL 3.• Integral time.- Parameter 21-22 Ext. 1 Integral Time forEXT CL 1.- Parameter 21-42 Ext. 2 Integral Time forEXT CL 2.- Parameter 21-62 Ext. 3 Integral Time forEXT CL 3.The PID differentiation time is set to 0 in the followingparameters:• Parameter 21-23 Ext. 1 Differentation Time for EXTCL 1.• Parameter 21-43 Ext. 2 Differentation Time for EXTCL 2.• Parameter 21-63 Ext. 3 Differentation Time for EXTCL 3 are set to value 0 (zero).• Parameter 21-20 Ext. 1 Normal/Inverse Control forEXT CL 1.• Parameter 21-40 Ext. 2 Normal/Inverse Control forEXT CL 2.• Parameter 21-60 Ext. 3 Normal/Inverse Control forEXT CL 3.These calculated values are presented on the LCP and caneither be accepted or rejected. Once accepted, the valuesare written to the relevant parameters, and PID auto-tuning mode is disabled in parameter 21-09 PID AutoTuning. Depending on the system being controlled, thetime required to carry out PID auto-tuning could beseveral minutes.Before activating the PID auto-tuning, remove excessivefeedback sensor noise using the input filter (parametergroups 5-5* Pulse Input, 6-** Analog In/Out and 26-** AnalogI/O Option MCB 109, terminal 53/54 filter time constant,and pulse filter time constant #29/33).Parameter Description Programming GuideMG20OB02 Danfoss A/S © 05/2018 All rights reserved. 1693 3