Siemens VFD fault codes

Common causes

• Motor cable short circuit or earth fault
• Motor power doesn't match the drive
• Damaged power stage

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

• Deceleration too fast
• High supply voltage
• Regenerative load

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

• Supply failure or dip
• Missing phase

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

• Fan failure
• High ambient temperature
• Blocked air flow

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

• Drive overloaded
• Duty cycle too high

What to check

• Reduce load or duty cycle

Common causes

• Motor overloaded
• Wrong motor data

What to check

• Check motor data parameters and the load

Common causes

• One input phase missing

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

• Motor or cable insulation failure

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

• IGBT or gate driver failure
• Short circuit on the output

What to check

• Disconnect the motor; if the fault remains, the power board needs repair