Fanuc · R-30iB Mate + Mate Plus Robot
The V4 (Red) LED indicates that the DCLINK circuit inside the servo amplifier is charged to the specified voltage. If this LED does not light after the pre-charge sequence is finished, it suggests a problem with the DC link charging, potentially due to a short circuit or a defective charge current control resistor.
Click steps to track your progress.
Check the DC Link circuit for a short-circuit connection.
Replace the emergency stop unit, as the charge current control resistor may be defective within it.
Replace the servo amplifier.