DescriptionThe Yaskawa SGDM-15DN is an AC servo amplifier of the Sigma-II series for 400 V servo applications in the power range up to 1.5 kW. The SGDM series is technically based on the SGDH platform, meaning that alarms and troubleshooting are fully compatible with the SGDH series. The device is designed for precise axis control, high dynamics, and reliable continuous operation in industrial automation environments.OverviewDevice category: AC Servo Amplifier (Servopack)Series/Class: Sigma-II (SGDM), 400 V classPower rating: 1.5 kWDesign: compact, forced-air cooled, IP1XModel DesignationSGDM = Yaskawa Sigma-II Servopack (Compact Series)15 = Power level 1.5 kWD = 400 V classN = Interface/Version variantTechnical DataFeatureValueManufacturerYaskawa Electric CorporationInput voltage3 Ph 380–480 V AC, 50/60 HzInput current4.8 AOutput voltage3 Ph 0–480 V AC, 0–300 HzOutput current5.4 AOutput power1.5 kWAmbient temperature0–55 °CCoolingForced ventilationProtection classIP1XWeight / Dimensionsn. a.Connections & InterfacesL1 / L2 / L3 – 3-phase mains input 380–480 VU / V / W – Motor outputsB1 / B2 / B3 – Brake resistor / RegenerationCN1 – Control and I/O interface (24 V DC)CN2 – Encoder connectionCN3 – RS-232C / Parameter setting (SigmaWin+)LED display – Status and alarm codesControl Board / AssembliesAssemblyDescriptionQuantityControl boardControl, logic, and communication1Power boardOutput stage for 400 V power class1DC linkCapacitors / Energy buffer1Power sectionCompact power section with heat sink1Alarms & TroubleshootingCodeDesignationTypical FindingCheckRemedyA.02Parameter BreakdownEEPROM data faultyInitialization (Fn005)Reload parametersA.05Combination ErrorMotor/Drive incompatibleCheck motor typeUse suitable motorA.10Overcurrent / OverheatOvercurrent or overtemperatureCheck U/V/W, loadCheck power sectionA.30Regeneration ErrorError in the regeneration pathCheck RB circuitRepair driveA.32Regenerative OverloadRegeneration too highCheck load profileReduce loadA.40OvervoltageDC link voltage too highMeasure mains voltageCheck supplyA.41UndervoltageSupply too lowCheck inputStabilize mainsA.51OverspeedEncoder or phase errorCheck encoderCorrect wiringA.71Overload 1Short-term overloadCheck current curveCheck mechanicsA.C9Encoder Comm ErrorEncoder communication disturbedCheck cable / shieldingReplace cableTypical ApplicationsCNC axes in the 400 V power range up to 1.5 kWAutomation and handling systemsPositioning axes with higher DC link voltageSpecial machinery and industrial manufacturingService NotesSave parameters before servicingRegularly check encoder and motor cablesKeep fans and cooling channels cleanNo insulation measurement (Megger) while installedAlways check mechanics and ramps in case of overcurrent or regeneration alarmsRepair DescriptionInput check: Visual inspection, measurement of mains and DC link voltage, short-circuit test on U/V/WDisassembly & Cleaning: Opening the housing, cleaning the boards, checking the cooling surfacesAnalysis: Checking the power stage, capacitors, current measurement, and control logicRepair: Replacement of defective power components and aged componentsTesting & Load Test: Test run with reference motor, monitoring current and temperatureLong-term Test & Completion: Continuous operation under load, documentation of measurement results