Danfoss VLT Series Operating Instructions Manual

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Danfoss VLT Series Operating Instructions Manual Manual pdf 17 page image

7 TroubleshootingLED No. Indication Fault Possible Cause Measures Comments1 Green LED twinkling No output voltage Signal input "Enable"not activeApply 10-28 V to signalinput "Enable"Also possible: connect12 V auxiliary voltagedirectly at the signalconnector (X3).2 Green LED blinking Reduced output voltage Signal input "300V" notactiveApply 10-28 V to signalinput "300 V", if fulloutput voltage(Setpoint Uo nominal) isdesiredAlso possible: connect12 V auxiliary voltagedirectly at the signalconnector (X3).3 No LED active No output voltage • No AC input voltage• Phases missingCheck AC input voltage If the power supplymodule's external fuseis blown, there is afailure in the powersupply module. Sendthe power supplymodule to Danfoss.4 Red LED blinking Output voltage possiblyreducedOutput current too high Check if output currentis higher than current Iolimitation–5 Red LED blinking Output voltage possiblyreduced• Fan blocked• Fan speed reduced• Check if fan ismechanically locked,e.g. by partsreaching inside thepower supply (fan)• Send the powersupply module toDanfoss for the fanto be replacedIf the fan is blocked, theoutput current isautomatically limited to4 A.6 Red LED blinking Output voltage possiblyreducedInternal heatsinktemperature too high• Check if air inlet andoutlet are free• Check if the ambienttemperature is toohighIf the temperature isabove "Warning Level",the output current islimited to 4 A.7 Red LED active No output voltage Internal heatsinktemperature too high• Check if air inlet andoutlet are free• Check if the ambienttemperature is ≤ therated ambienttemperature of thespecificationIf temperature is above"Fault Level", the outputis switched off8 Red LED active No output voltage Internal failure Contact Danfoss-Service If the external fuse isbroken, do not try toreturn the mainsvoltage to the powersupply module.Table 7.1 TroubleshootingTroubleshooting VLT® ISD Power Supply Module Operating InstructionsMG75H102 - VLT® is a registered Danfoss trademark 177 7