192 YASKAWA TM.V1000.01 V1000 Drive Installation & Start-Up Manual (Preliminary 01-19-07)5.3 Main Circuit Test Procedure5.3 Main Circuit Test ProcedureThis section describes test procedures that may assist in identifying defective drivehardware.WARNING! Electrical Shock Hazard. Do not touch terminals before the capacitors have fullydischarged. Failure to comply could result in death or serious injury. Before wiring terminals,disconnect all power to the equipment. The internal capacitor remains charged even after thedrive input power is turned off. The charge indicator LED will extinguish when the DC busvoltage is below 50 Vdc. To prevent electric shock, wait at least five minutes after all indicatorsare off and measure the DC bus voltage level to confirm safe level.WARNING! Electrical Shock Hazard. Do not allow unqualified personnel to perform work onthe drive. Failure to comply could result in death or serious injury. Installation, maintenance,inspection and servicing must be performed only by authorized personnel familiar withinstallation, adjustment and maintenance of AC drives.Table 5.4 Main Circuit Test ProcedureCheck ProcedureMeasure DCBus Voltage1. Set the digital multimeter to its highest Vdc scale.2. Measure between ⊕ 1 and (-) for the following check:• Place the positive (red) meter lead on ⊕ 1.• Place the negative (black) meter lead on (-).3. If the measured voltage is < 10 Vdc, it is safe to work inside the drive.If the measured voltage is 10 Vdc or higher, wait until the DC Bus has completelydischarged to begin work inside the drive.
