Danfoss TTS400

1.8 Electrical Isolation
BeforeservicingtheCompressor,isolatethecompressorpowerbycompletingthefollowingsteps:
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• • • DANGER! • • •
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Thisequipmentcontainshazardousvoltagesthatcancauseseriousinjuryordeath.Onlyqualifiedandtrainedpersonnel
shouldworkonDanfossLLCequipment.
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Alwayswearappropriately-ratedsafetyequipmentwhenworkingaroundequipmentand/orcomponentsenergizedwith
highvoltage.
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RemovingtheMainsInputCoverwillexposethetechniciantoahighvoltagehazardofupto632VAC.EnsuretheMains
InputpoweristurnedoffandlockedoutbeforeremovingtheMainsInputCover.
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1. TurnofftheMainsInputpowertothecompressor.
2. LockOut/TagOut(LOTO)themainsdisconnecttoensurenoaccidentalorunauthorizedreapplication
oftheMainsInputpowercanoccur.
NOTE
TheMainsInputfast-actingfusesareinstalledinthepowerpanelforallcompressormodelsexcepttheTTS300/TGS230.
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3. RemovetheMainsCoveronly.RefertoSection4.1.1MainsInputCoveronpage52.
4. Usinganappropriately-ratedvoltagemeter,confirmtheabsenceofACvoltage.
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• • • DANGER! • • •
DonottouchanycomponentswhenremovingtheMainsInputCover.
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5. IfACvoltageisnotpresent,reinstalltheMainsInputcoverandwaitatleast20minutesbefore
removingeithertheMainsInputorTopSideCover.IfACvoltagestillexists,gobacktoStep2to
determinewhythecompressorvoltageisnotisolated.
6. RemovetheTopCover,takingparticularcarenottotouchANYcomponentsunderneath.Referto
Section4.1.2TopCoveronpage53.
7. Usinganappropriately-ratedvoltagemeter,checktheDCBusBarsforDCvoltagelevel.Ifthevoltageis
above30voltsdirectcurrent(VDC),waitfive(5)minutesandrecheckuntilvoltageisbelow30VDC.
RefertoFigure1-6DCBusVoltageTestPointsonpage23.
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• • • CAUTION • • •
Evenatlowvoltages,cautionshouldbeusedaroundthecapacitorstoavoidquickdischargeevents,whichcanleadtoreducedreliability.
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Page 22 of 294 - M-SV-001-EN Rev. H 1/23/2023