Yaskawa VFD fault codes

Common causes

• Short circuit or earth fault on the output
• Acceleration time too short
• Damaged IGBT or current sensor

What to check

• Disconnect the motor cable and run the drive without load: if the fault stays, the drive itself is faulty
• Megger the motor and cable for insulation or phase-to-phase faults
• Increase acceleration/deceleration time; check for mechanical jams

Common causes

• Motor or cable insulation failure
• Moisture in the motor

What to check

• Megger the motor and cable to earth
• Check for water or dust in the motor terminal box
• If insulation is fine, the output IGBT or current sensor may be faulty

Common causes

• Deceleration too fast
• High or unstable supply voltage
• Braking resistor missing or faulty

What to check

• Increase the deceleration time or enable the stall/overvoltage prevention function
• Check the braking resistor and braking transistor (if fitted)
• Measure the supply voltage – it should be within the drive's rating

Common causes

• Low supply voltage or phase loss
• Faulty pre-charge circuit

What to check

• Measure all three input phases under load
• Check input fuses, contactor and loose terminals
• If the supply is fine, check the DC bus capacitors and pre-charge circuit

Common causes

• Fault in the drive's internal power supply (SMPS)

What to check

• Check the 24 V control supply and external loads on it
• Usually needs control/power board repair

Common causes

• Faulty pre-charge relay or resistor

What to check

• Needs power board inspection

Common causes

• Fan failure or blocked heatsink
• High ambient temperature

What to check

• Clean the heatsink and check that the cooling fan runs
• Check the panel temperature and ventilation
• Reduce the load or carrier frequency

Common causes

• Motor overloaded
• Wrong motor rated current setting

What to check

• Check E2-01 (motor rated current) and the load

Common causes

• Load too high for the drive
• Carrier frequency too high

What to check

• Reduce load or carrier frequency, or use a larger drive

Common causes

• Missing supply phase
• Loose input wiring
• Aged DC bus capacitors

What to check

• Measure all three input phases under load
• Check input fuses, contactor and loose terminals
• If the supply is fine, check the DC bus capacitors and pre-charge circuit

Common causes

• Broken motor cable or winding
• Loose output terminal

What to check

• Check motor cable continuity and terminals
• Measure the motor windings

Common causes

• Output short circuit
• Failed IGBT

What to check

• Disconnect the motor and test: if SC remains, the IGBT/power board needs repair

Common causes

• Control board fault
• Electrical noise

What to check

• Check grounding and shielding
• Repeating CPF errors need control board repair