12.2 Converter Faults12 - 312.2 Converter FaultsIf a fault occurs during operation, protective functions are activated depending on the fault and operation isstopped. The contents of the faults are displayed numerically on the 7-segment display.Table 12.1 Converter FaultsFault No. Name Meaning Corrective ActionsOvercurrent Output current exceeded overcurrentdetection level.S Check the wiring.S Check the input supply voltage.S Check the AC reactor.S Check the load shaft (Inverter, Servo)capacity.Main circuit fuseblown Main circuit fuse was blown. Check for damaged transistor, loadshort circuit, ground short, etc.Overload Output current exceeded overload lev-el.S Reduce the load.S Check the load shaft (Inverter, Servo)capacity.Output overvoltageOutput voltage exceeded overvoltagelevel.Detection level:200 V class: Approx. 400 V400 V class: Approx. 800 VS Check the input supply voltage.S Check the load shaft(Inverter, Servo) capacity.Main circuit under-voltageMain circuit output voltage becamelower than undervoltage detection lev-el.Check the input supply voltage.Control circuit un-dervoltageControl circuit power supply becamelower than undervoltage detection lev-el. Check the control supply voltage.Servo unit powersupply faultControl supply voltage supplied to Ser-vo Unit was not normal.Check the control supply voltage.Power supply fre-quency faultExcessive power supply frequencydeviation (50 Hz or 60 Hz ±5%) Check the input power waveform.Initial chargingfaultCharging of main circuit capacitor wasnot completed within set time. Replace the Unit.Power supply openphaseAn open phase occurred at input sup-ply.S Check the input supply voltage.S Check the wiring.Built-in MC opera-tion fault Magnetic contactor did not function. Replace the Unit.Heatsink overheat1Heatsink temperature exceeded upperlimit (minor fault). Check the ambient temperature for ef-Heatsink overheat2Heatsink temperature over upper limitcontinued for one minute or longer.Check the ambient temperature for effective cooling.Heatsink thermis-Thermistor for heatsink temperaturedetection was disconnected. Replace the unit.Heatsink thermistor disconnection The ambient temperature is low(−20°C (−4°F) or below).Raise the ambient temperature to above−20°C (−4°F).Control PCB tem-perature fault 1Control PCB temperature exceeded80°C (176°F) (minor fault). Check the ambient temperature for ef-Control PCB tem-perature fault 2Control PCB temperature exceeded85°C (185°F).Check the ambient temperature for effective cooling.12
