3-3 When an Inverter Overvoltage Trip Occurs 3-3 When an Inverter Overvoltage Trip Occurs In principle, an Inverter overvoltage trip occurs when the Inverter cannot completely absorb a volt- age rise due to excessive regenerative energy. As a countermeasure, review the resistance of the Braking Resistor, model and number of Regen- erative Braking Units, as well as Inverter deceleration time. Wire breakage in the Breaking Resistor, incorrect wiring, and/or improper DIP switch settings can be also considered as a cause of an In- verter overvoltage trip. Use the flowchart to diagnose the problem: 3 Maintenance Operations Overvoltage trip occurs.
During Inverter deceleration, is the operation LED indicator lit? YES The Braking Resistor model selection is improper. Review resistor selection, or extend the inverter deceleration time. (There may be a wire breakage in the Braking Resistor.) NO NO Is the operation LED indicator on the master unit (or the unit in single operation) unlit? YES NO NO Are the DIP switches set to master? Are the DIP switches set to slave? Set the DIP switches to slave. YES YES Set the DIP switches to master. Is wiring between the P and N terminals, as well as the control circuit terminals connection correct? NO YES Be sure to wire correctly and securely. The Regenerative Braking Unit is defective.
Replace or repair the unit. 3-3