Danfoss TTS300

8. RemovethebearingPWMamplifierfromJ1oftheBackplane.
4.28.4.2 PWM Amplifier Installation
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NOTE
PriortoreplacingaPWM,verifythebearingcoils.RefertoSection4.29.3.1BearingCoilVerificationonpage230.
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1. Cleanthesurfaceofthecompressorwheretheheatsinkplatecontactsthehousingandcleanthe
matingsurfaceofthePWMifitistobereused.
2. SpreadathinanduniformcoatofDowCorningSiliconeHeatSinkpaste(orequivalent)entirelyover
thePWMmountingsurfacewhereitcontactsthecompressorhousing.
3. CheckthattheM5x10groundfasteneratthelowerrightoftheBackplaneistightbeforereplacingthe
PWM.Torqueto3Nm(27in.lb).
4. AligntheheatsinkofthePWMwiththetwo(2)guidepinsinthemaincompressorhousing.
5. InsertthePWMintotheJ1connectoroftheBackplane.
6. SecuretheheatsinkofthePWMtothemaincompressorhousingwiththreeM5x10fasteners.Torque
to4.5Nm(40in.lb.).
7. EnsuretheheatsinkofthePWMisfirmlyseatedagainstthemaincompressorhousing.
8. Connectthetwo(2)connectorsforthePWMandbearingpowerfeedthroughs.
9. InstalltheBMCC.RefertoSection4.27BMCConpage220.
10. InstalltheSerialDriver.RefertoSection4.26.4SerialDriverRemovalandInstallationonpage218.
NOTE
PerformabearingcalibrationafterreplacingthePWMtoverifyfunctionality.RefertoSection5.3BearingCalibrationonpage263.
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11. InstallServiceSideCover.RefertoSection4.1.3.1ServiceSideCoverRemovalandInstallationonpage
54.
12. Installtopcovers.RefertoSection4.1CompressorCoversonpage52.
13. Returnthecompressortonormaloperation.
4.28.4.3 PWM Torque Specifications
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Table 4-44 PWM Torque Specifications
Description Nm Ft.Lb. In.Lb.
BackplaneMounting/Groundfastener,M5x10 3 - 27
PWMMounting/heatsinkfastener,M5x10 4.5 - 40
Coverfastener,M5x15 1.5 - 13
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M-SV-001-EN Rev. H-1/23/2023 Page 229 of 294