7.2 InspectionYASKAWA ELECTRIC SIEP C710616 27C YASKAWA AC Drive A1000 Technical Manual 347Periodic Inspection &Maintenance77.2 InspectionPower electronics have limited life and may exhibit changes in characteristics or performance deterioration after years ofuse under normal conditions. To help avoid such problems, it is important to perform preventive maintenance andperiodic inspection on the drive.Drives contain a variety of power electronics such as power transistors, semiconductors, capacitors, resistors, fans, andrelays. The electronics in the drive serve a critical role in maintaining 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 one to two years after installation.◆ Recommended Daily InspectionTable 7.1 outlines the recommended daily inspection for Yaskawa drives. Check the following items on a daily basis toavoid premature deterioration in performance or product failure. Copy this checklist and mark the “Checked” columnafter each inspection.Table 7.1 General Recommended Daily Inspection ChecklistInspection Category Inspection Points Corrective Action CheckedMotor Inspect for abnormal oscillation or noise coming from the motor.• Check the load coupling.• Measure motor vibration.• Tighten all loose components.CoolingInspect for abnormal heat generated from the drive or motor andvisible discoloration.• Check for excessive load.• Loose connections• Check for dirty heatsink or motor.• Ambient temperatureInspect drive cooling fan and circulation fan operation. • Check for clogged or dirty fan.• Check fan operation drive parameter.Environment Verify the drive environment complies with the specifications listedin Installation Environment on page 40.• Eliminate the source of contaminants or correct poorenvironment.Load The drive output current should not be higher than the motor or driverating for an extended period of time.• Check for excessive load.• Check the motor parameter settings of the drive.Power Supply Voltage Check main power supply and control voltages.• Correct the voltage or power supply to within nameplatespecifications.• Verify all main circuit phases.
