Siemens fault record

F0002: DC-Link Overvoltage Fault

MICROMASTER drive trips on F0002 during ramp-down, OFF3 fast stop, fan coast-down, pump check-valve slam, regenerative load or a high-line condition.

Fault-code repair decision page9 min read

Scope of this technical record

F0002 overvoltage routing for MICROMASTER drives, prioritising deceleration energy, OFF3 ramp, load inertia and brake/DC-link evidence before board replacement.

Safety boundary

Treat the DC link as hazardous. Overvoltage events can involve stored energy and regeneration; verify discharge before access.

Why F0002 is often an application-energy problem

A F0002 report during deceleration usually asks whether the machine is returning more energy to the DC link than the drive can manage. For fan and pump work, this means looking at inertia, stop command, ramp time, valve/damper behaviour and any braking option before suspecting the control board.

If F0002 appears at idle or power-up, the route changes. High line voltage, bus measurement, capacitor condition or internal DC-link sensing becomes more relevant. The same code therefore needs a timing map.

F0002 timing split

Observed behaviourFirst suspect areaWhat confirms the route
Only during normal stopDecel ramp and inertiaLonger ramp or load change prevents the trip
During OFF3 fast stopFast-stop ramp energyP1135/stop-mode evidence matches trip timing
At idle/power-upHigh line or bus sensingInput/DC-link evidence abnormal without regeneration
After braking hardware changeBrake resistor/chopper/wiringBrake path evidence is open, misrated or not switching

Field record checklist

  • Stop mode
  • Deceleration/OFF3 ramp
  • Load inertia
  • Input voltage
  • Brake resistor/chopper evidence
  • DC-link reading
  • Fault history

Technical basis and reference documents

This is an independent editorial technical reference. Original manufacturer documentation remains controlling for installation, repair and commissioning decisions.

MICROMASTER 440 operating instructionsSiemens

Public Siemens documentation links too-short ramp-down time to A0502/F0002 behaviour.

Diagnostic workflow