6.2 InspectionPower electronics have limited life and may exhibit changed characteristics or performancedeterioration after years of use under normal conditions. To help avoid such problems, it isimportant to perform preventive maintenance and periodic inspection on the drive.Drives contain a variety of power electronics such as power transistors, semiconductors,capacitors, resistors, fans, and relays. The electronics in the drive serve a critical role inmaintaining proper motor control.Follow the inspection lists provided in this chapter as a part of a regular maintenance program.Note: The drive will require more frequent inspection if it is placed in harsh environments,such as:• High ambient temperatures• Frequent starting and stopping• Fluctuations in the AC supply or load• Excessive vibrations or shock loading• Dust, metal dust, salt, sulfuric acid, chlorine atmospheres• Poor storage conditions.Perform the first equipment inspection 3 months after installation.u Recommended Daily InspectionTable 6.1 outlines the recommended daily inspection for Yaskawa drives. Check the followingitems on a daily basis to avoid premature deterioration in performance or product failure. Copythis checklist and mark the “Checked” column after each inspection.WARNING! Electrical Shock Hazard. Do not connect or disconnect wiring while the power is on. Failure tocomply can result in serious personal injury. Before servicing the drive, disconnect all power to the equipment.The internal capacitor remains charged even after the power supply is turned off. The charge indicator LEDwill extinguish when the DC bus voltage is below 50 Vdc. To prevent electric shock, wait at least one minuteafter all indicators are OFF and measure the DC bus voltage level to confirm safe level.Table 6.1 General Recommended Daily Inspection ChecklistInspectionCategory Inspection Points Corrective Action CheckedMotor • Inspect for abnormal oscillation or noisecoming from the motor.• Check the load coupling.• Measure motor vibration.• Tighten all loose components.Cooling • Inspect for abnormal heat generatedfrom the drive or motor and visiblediscoloration.• Check for excessive load.• Loose connections• Check for dirty heatsink or motor.• Ambient temperatureCooling Fan • Inspect drive cooling fan operation. • Check for clogged or dirty fan.• Check fan operation drive parameter.Environment • Verify the drive environment complieswith the specifications listed in theInstallation section of this manual.• Eliminate the source of contaminantsor correct poor environment.6.2 InspectionYASKAWA ELECTRIC TOEP C710606 25B YASKAWA AC Drive J1000 Installation & Start-Up Manual 1556 Periodic Inspection &Maintenance
