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

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Danfoss VLT AQUA Drive FC 202 Programming Manual Manual pdf 175 page image

3.22 Parameters 25-** Cascade ControllerParameters for configuring the Basic Cascade Controller for sequence control of multiple pumps. For a more applicationoriented description and wiring examples, see Chapter Application Examples, item Basic Cascade Controller in the DesignGuide.To configure the Cascade Controller to the actual system and the desired control strategy, it is recommended to follow thebelow sequence, starting with parameter group 25-0* System Settings and next parameter group 25-5* Alternation Settings.These parameter can normally be set in advance.Parameters in 25-2* Bandwidth Settings and 25-4* Staging Settings, will often be dependent on the dynamic of the systemand final adjustment to be done at the commissioning of the plant.NOTICEThe Cascade Controller is supposed to operate in closed loop controlled by the built-in PI controller (Closed Loopselected in parameter 1-00 Configuration Mode). If Open Loop is selected in parameter 1-00 Configuration Mode, all fixedspeed pumps will be destaged, but the variable speed pump will still be controlled by the frequency converter, now asan open loop configuration:130BA279.122 32Off AtstagingAtcommandAt stagingorcommandExternalAlt. timerintervalP 25-52SleepmodePredefinedtimerP 25-54Disabled EnabledSlow QuickNo YesDisabled EnabledDirect on lineEnabledDisabledCascade controller (P 25-00):Number of pumps (P 25-06):Motor start (P 25-02):Pump cycling (P 25-04):Fixed lead pump (P 25-05):Lead pump alternation (P 25-50):Alternation Event (P 25-51):Alt. if capacity<50% (P 25-55):Staging mode at alternation (P 25-56):Config. of cascade controllerSoft StarterConfiguration mode (P 1-00): Open Loop Closed LoopIllustration 3.71 Cascade Controller Sample Set-upParameter Description Programming GuideMG20O702 Danfoss A/S © Rev. 2014-01-21 All rights reserved. 1733 3