F30002 — Power unit: DC link voltage overvoltage

The manuals print this code as "Power unit: DC link voltage overvoltage": the power unit has detected an overvoltage condition in the DC link. The same code is raised by the power units of every SINAMICS family listed on this page, and the manuals describe the condition identically — they differ only in which causes they enumerate. When the fault trips, the drive coasts down and the fault must be acknowledged immediately before the drive will start again. The DC link voltage present at the instant of the trip is stored as the fault value, so the stored number shows how high the voltage actually climbed.

• The motor regenerates too much energy.
• The supply voltage at the device (line connection) is too high.
• A line phase is interrupted.
• When the drive operates with a Voltage Sensing Module (VSM), the phase assignment L1, L2, L3 at the VSM differs from the phase assignment at the power unit.
• The G120 and G120XA manuals add two setting-related causes: the DC link voltage control is switched off, or the dynamic response of the DC link voltage controller is excessive or insufficient.

1. Increase the ramp-down time (p1121 on the G120 and G120XA).
2. Set the rounding times p1130 and p1136. This is particularly recommended in U/f operation to relieve the DC link voltage controller with rapid ramp-down times of the ramp-function generator.
3. Activate the DC link voltage controller — p1240, or p1280 in U/f operation.
4. If the controller response is excessive or insufficient, adapt its dynamic response with p1243, p1247, p1283 and p1287 (G120/G120XA remedy).
5. If the motor really regenerates too much energy, use a brake resistor or an Active Line Module; for the Active Line Module, increase the current limit of the infeed or use a larger component.
6. Check the line supply and the DC link voltage and set p0210 as low as possible (the G120/G120XA remedy here also refers to A07401 and p1294 = 0).
7. Check and correct the phase assignment: with a Voltage Sensing Module (VSM), compare the assignment L1, L2, L3 at the VSM with the assignment at the power unit; the G120/G120XA remedy is to check and correct the phase assignment at the power unit.
8. Check the line supply phases — an interrupted line phase also raises this fault.

• The drive stores the fault value in r0949; interpret the value as a decimal number.
• Content: the DC link voltage at the time of trip, scaling 0.1 V — each count corresponds to 0.1 V of DC link voltage.

• r0949 — fault value: read the DC link voltage that was present at the moment of the trip (decimal interpretation).
• p1121 — ramp-function generator ramp-down time: increase it as the first remedy.
• p1130 — ramp-function generator initial rounding-off time: set it as the rounding-time remedy.
• p1136 — OFF3 initial rounding-off time: set it together with p1130.
• p0210 — drive unit line supply voltage: check it against the actual line voltage and set it as low as possible.
• p1240 — Vdc controller or Vdc monitoring configuration: use it to activate the DC link voltage controller.
• p1280 — Vdc controller configuration (U/f): the U/f counterpart for activating the controller.
• p1243 — Vdc_max controller dynamic factor: adapt it when tuning the controller's dynamic response.
• p1247 — Vdc_min controller dynamic factor (kinetic buffering): adapt it together with p1243.
• p1283 — Vdc_max controller dynamic factor (U/f): the U/f counterpart of p1243.
• p1287 — Vdc_min controller dynamic factor (kinetic buffering) (U/f): the U/f counterpart of p1247.
• p1294 — Vdc_max controller automatic detection ON signal level (U/f): the remedy that sets p0210 low names p1294 = 0 here, together with alarm A07401.

The acknowledgement for this fault is immediate: clear the overvoltage condition, then acknowledge the fault directly on the operator panel or in the commissioning tool — only then can the drive be started again.