Siemens SINAMICS G120 troubleshooting
SINAMICS G120 is Siemens’ modular converter: a Control Unit (CU240B-2, CU240E-2 and others) on a Power Module. Messages starting with F are faults: the converter stops the motor and the fault must be acknowledged. Messages starting with A are alarms: they do not stop the drive, need no acknowledgment and clear when the cause goes. F3xxxx codes come from the Power Module; F07xxx codes come from the drive control.
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Try Free Drive Diagnostic Upload a photo of the alarm screen, the fault history or a data export. InduQT compares the evidence and suggests the next useful checks.
How it reports faults
- Alarms show as Axxxxx and faults as Fxxxxx on the Operator Panel and in STARTER or Startdrive.
- r0945 holds the fault codes, r0948 the time each fault was received, and r0949 the fault value: extra data such as the phase that tripped (F30001) or the DC link voltage at the trip (F30002).
- The fault buffer holds up to eight active faults; acknowledged faults move to the fault history. p0952 counts fault cases, and setting it to 0 clears the buffer.
- r2122 holds alarm codes in the alarm buffer. r2114 is the system runtime used to time-stamp faults and alarms.
- Most faults described here react with OFF2 (pulses blocked, motor coasts) and acknowledge IMMEDIATELY once the cause is gone.
Fault codes
| Code | Name |
|---|---|
| F30001 | Power unit: Overcurrent |
| F30002 | DC link voltage, overvoltage |
| F30003 | DC link voltage, undervoltage |
| F30005 | Power unit: Overload I2t |
| F07801 | Motor overcurrent |
| F07900 | Motor blocked |
| A07910 | Motor overtemperature |
| F01910 | Setpoint timeout (fieldbus) |
| F03505 | Analog input, wire break |
| A05000 | Power Module overtemperature |
| F06310 | Supply voltage (p0210) incorrectly set |
| F07011 | Motor overtemperature |
| A07012 | I2t Motor Module overtemperature |
| F07016 | Motor temperature sensor fault |
| F07320 | Automatic restart aborted |
| A07400 | DC link voltage maximum controller active |
| A07409 | U/f control, current limiting controller active |
| A07805 | Power unit overload I2t |
| F07806 | Regenerative power limit exceeded |
| F07807 | Short-circuit detected |
| F07860 | External fault 1 |
| F07901 | Motor overspeed |
| F07902 | Motor stalled |
| F08501 | PROFINET setpoint timeout |
| F30004 | Inverter (heat sink) overtemperature |
| F30011 | Line phase failure |
| F30015 | Motor cable phase failure |
| F30021 | Power unit: Ground fault |
| F30027 | DC link pre-charging time monitoring |
| A30502 | DC link overvoltage (alarm) |
Evidence to collect
- Operator Panel photo or Startdrive/STARTER export showing all F and A messages
- r0945, r0948 and r0949 for each fault
- Control Unit and Power Module order numbers and firmware version
- Motor data (p0304–p0311) and the motor rating plate
- p1120/p1121 ramp times, p0640 current limit, p1240/p1280 Vdc controller settings
- What the machine was doing at the trip
Work on fuel trains, burners, pressure vessels and electrical equipment must be done by qualified personnel following the manufacturer’s documentation and local codes. Never bypass a safety device or interlock.