Danfoss VLT AQUA Drive FC 202 Design Manual

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

Contents

Protective measures• Qualified and skilled personnel are required forinstallation and commissioning of safetyengineering systems.• The unit must be installed in an IP54 cabinet orin an equivalent environment. In specialapplications, a higher IP degree is required.• The cable between terminal 37 and the externalsafety device must be short-circuit protectedaccording to ISO 13849-2 table D.4.• When external forces influence the motor axis (forexample, suspended loads), to eliminate potentialhazards, additional measures are required (forexample, a safety holding brake).2.7 Fault, Warning and Alarm FunctionsThe frequency converter monitors many aspects of systemoperation including mains conditions, motor load andperformance, as well as converter status. An alarm orwarning does not necessarily indicate a problem with thefrequency converter itself. It may be a condition outside ofthe converter that is being monitored for performancelimits. The converter has various pre-programmed fault,warning and alarm responses. Select additional alarm andwarning features to enhance or modify systemperformance.This section describes common alarm and warningfeatures. Understanding that these features are availablecan optimise a system design and possibly avoidintroducing redundant components or functionality.2.7.1 Operation at OvertemperatureBy default, the frequency converter issues an alarm andtrip at overtemperature. If Autoderate and Warning isselected, the frequency converter will warn of thecondition but continue to run and attempt to cool itself byfirst reducing its switching frequency. Then, if necessary, itreduces the output frequency.Autoderating does not replace the user settings forderating for ambient temperature (see chapter 5.3 Deratingfor Ambient Temperature).2.7.2 High and Low Reference WarningIn open-loop operation, the reference signal directlydetermines the speed of the converter. The display showsa flashing reference high or low warning when theprogrammed maximum or minimum is reached.2.7.3 High and Low Feedback WarningIn closed-loop operation, the selected high and lowfeedback values are monitored by the converter. Thedisplay shows a flashing high or flashing low warningwhen appropriate. The converter can also monitorfeedback signals in open-loop operation. While the signalsdo not affect the operation of the converter in open loop,they can be useful for system status indication locally orvia serial communication. The frequency converter handles39 different units of measure.2.7.4 Phase Imbalance or Phase LossExcessive ripple current in the DC bus indicates either amains phase imbalance or phase loss. When a powerphase to the converter is lost, the default action is to issuean alarm and trip the unit to protect the DC buscapacitors. Other options are to issue a warning andreduce output current to 30% of full current or to issue awarning and continue normal operation. Operating a unitconnected to an imbalanced line may be desirable untilthe imbalance is corrected.2.7.5 High Frequency WarningUseful in staging on additional equipment such as pumpsor cooling fans, the converter can warm when the motorspeed is high. A specific high frequency setting can beentered into the converter. If the output exceeds the setwarning frequency, the unit displays a high frequencywarning. A digital output from the converter can signalexternal devices to stage on.2.7.6 Low Frequency WarningUseful in staging off equipment, the converter can warnwhen the motor speed is low. A specific low frequencysetting can be selected for warning and to stage offexternal devices. The unit will not issue a low frequencywarning when it is stopped nor upon start up until afterthe operating frequency has been reached.2.7.7 High Current WarningThis function is similar to high frequency warning, except ahigh current setting is used to issue a warning and stageon additional equipment. The function is not active whenstopped or at start up until the set operating current hasbeen reached.Product Overview Design GuideMG20N602 Danfoss A/S © 09/2014 All rights reserved. 332 2