Siemens SINAMICS G120 fault F30002: DC link voltage, overvoltage
Fault F30002 on a SINAMICS G120 means the Power Module detected overvoltage in the DC link and switched off. Siemens lists too much regenerated energy, high line voltage, an interrupted line phase and the DC link voltage controller being off or poorly tuned. r0949 holds the DC link voltage at the trip in 0.1 V units.
Diagnose this with AI
Try Free Drive Diagnostic Upload a keypad photo, the fault history or a parameter export from your Siemens SINAMICS G120. InduQT compares the evidence and suggests the next useful checks.
When it happens
- Ramp-down or stopping, especially high-inertia loads
- Running with an overhauling load
- Any time if the line voltage is too high
Likely causes and checks
1Ramp-down too fast for the inertia
- Points to it
- Trips only during ramp-down or speed reduction.
- Check
- Increase p1121 (ramp-down time); in U/f operation also set rounding times p1130/p1136.
2Vdc_max controller switched off
- Points to it
- p1240 (vector) or p1280 (U/f) is 0 and no braking resistor is fitted.
- Check
- Activate the DC link voltage controller (p1240 or p1280 per control mode).
3Vdc controller dynamic response unsuitable
- Points to it
- Controller is active (A07400 appears) but trips still occur.
- Check
- Adapt the controller dynamics (p1243, p1247, p1283, p1287) per the List Manual.
4Line voltage too high or p0210 set wrong
- Points to it
- Trips at constant speed or while stopped.
- Check
- Measure the supply and compare with p0210 (unit supply voltage).
5Line phase interrupted or phase assignment wrong
- Points to it
- Trips together with line-side problems.
- Check
- Check the line phases and the phase assignment at the Power Module.
Telling it apart
- A07400 (DC link voltage maximum controller active) is an alarm that the controller is holding the voltage down; F30002 is the trip when it could not.
- A30502 is a DC link overvoltage alarm; Siemens’ remedy is to check the supply voltage p0210 and the line reactor sizing.
- F07806 (regenerative power limit exceeded) points to the Power Module’s energy recovery capability rather than the DC link limit.
Relevant parameters
| Parameter | Name | Why it matters |
|---|---|---|
| p1121 | Ramp-function generator ramp-down time | Factory setting 10 s. |
| p1240 / p1280 | Vdc controller configuration (vector / U/f) | Activates the Vdc_max controller; set to 0 only when it is not wanted. |
| p1130 / p1136 | Ramp rounding times | Recommended in U/f operation with fast ramp-down. |
| p0210 | Unit supply voltage | Must match the actual line voltage. |
Evidence to collect
- r0949 for F30002 (DC link voltage at trip)
- p1121, p1130, p1136 settings
- p1240 or p1280 setting and any A07400 history
- Measured supply voltage and p0210
- Whether a braking resistor is fitted
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