Danfoss TTS400

4. RoutethecablesthroughthecablepassagebesidetheDC-DCConverter,downintotheserviceside.
RefertoFigure1-16CablePassageonpage28.
NOTE
Whenchecksarecomplete,disconnectandremovethetestharness.

5. ReinstalltheTopCoverandMainsInputCover.Referto4.1CompressorCoversonpage52.
6. ReapplyACpowertotheCompressor.
7. InsertthepositivevoltmeterleadintotheDC(+)testharnesslead,andthenegativevoltmeterlead
intotheDC(-)testharnesslead.RefertoTable1-2ExpectedDCBusVoltageonpage29forthe
expectedDCbusvoltage.IftheDCbusvoltageisnotpresent,orifitisoutsidethe“ExpectedDCBus
Voltage”rangeshowninTable1-2ExpectedDCBusVoltageonpage29,verifyproperincomingAC
input,verifySCRGates,andverifySCRDiodes.IfincomingACpoweriscorrect,andtheSCRspassthe
diodeandgatetests,replacetheSoftStart.

NOTE
TherearenoreplaceablefusespresentintheOpen-TopSoftStart.

8. Whenfinished,removetheDCBusTestHarness.RefertoSection1.10.4GeneralDCBusTestHarness
Removal.
1.10.4 General DC Bus Test Harness Removal
1. Isolatethecompressorpowerasdescribedin1.8ElectricalIsolation.
• • • CAUTION • • •
UseyourESDwriststrapbeforetouchingtheSoftStartBoardoranyelectroniccomponents.

2. UseanESDstrapandattachitthecompressorhousingwhileremovingtheTestHarness.
3. ContinuetotheappropriatesectionbelowbasedontheparticularSoftStart.
1.10.5 DC Bus Test Harness Removal for Closed-Top Soft Starts
1. RemovetheDCbustestharnessfromthecablepassage.
2. Disconnectthetwo(2)plugsoftheDCBusTestHarnessfromtheSoftStart.
3. Disconnectthetwo(2)plugsofthecompressorcableharnessfromthecorrespondingsocketsofthe
DCBusTestHarness.
4. ReconnecttheJ1andJ7connectorsintotheSoftStart.
5. RemoveESDstrapfromthecompressorandyourself.
6. Installallcoversonthecompressor.RefertoSection4.1CompressorCoversonpage52.
7. Returnthecompressortonormaloperation.
1.10.6 DC Bus Test Harness Removal for Open-Top Soft Starts
1. RemovetheDCBusTestHarnessfromthecablepassage.
2. DisconnecttheplugoftheDCBusTestHarnessfromtheSoftStart.
3. DisconnecttheplugofthecompressorcableharnessfromthesocketoftheDCBusTestHarness.
4. ReconnectthecompressorcableharnessintotheJ8connectorontheSoftStart.
5. RemoveESDstrapfromthecompressorandyourself.
M-SV-001-EN Rev. H-1/23/2023 Page 31 of 294