Onsite Siemens drive diagnostics

SINAMICS G120 F30002 DC-link overvoltage when the machine stops?

The drive reports an excessive DC-link voltage, but the code does not identify the initiating condition on its own. If the trip appears as a load slows down, evidence about the stop sequence matters more than repeatedly clearing the alarm. West Engineering Systems offers onsite controls diagnostics to identify the fault and help determine next actions, based in Appleton, Wisconsin, with field service across the United States.

Discuss an F30002 Trip

Call (920) 851-6363 with the exact display message.

Was the drive accelerating, running or decelerating?

Siemens' CU240B-2/CU240E-2 list manual describes F30002 as “Power unit: DC link voltage overvoltage.” Possible contributing conditions include the supply and regenerated energy from the load; the applicable manual, topology and fault value must be checked for the installed variant. Do not infer a failed braking resistor or drive simply from this number.

Trip on a commanded stop

Note whether F30002 occurred during a normal stop, after an emergency stop, or after a different machine alarm. These are different sequences. Record what the machine was carrying and whether the load was overrunning; do not attempt a test stop just to recreate the trip.

Trip without deceleration

If the code appears at energization, during acceleration, or at steady speed, the deceleration hypothesis is not established. Preserve the exact time, drive status, available DC-link indications and earlier alarms for a qualified comparison with the supply and process.

Changes to equipment

Have drawings and records of recent motor, brake, load, supply or drive changes ready. A previously stable cycle that trips after a change calls for a different investigation from a trip on an unchanged process. A braking component may not even be fitted to this installation.

Onsite diagnostic goal: correlate the fault history and motion sequence with the actual G120 configuration and authorized measurements, then identify the likely fault area and next safe action.

What to gather before calling

  • Facility location, machine function and affected motor or conveyor.
  • Photo of F30002 and any fault value or preceding alarm already visible.
  • What happened immediately before the trip: start, run, normal stop or another event; whether it occurs only with a loaded machine.
  • Known Control Unit/Power Module order numbers, cycle history, drawings and existing project backup.

Different G120 symptom?

An F30001 power-unit overcurrent trip needs the overcurrent diagnostic guide. F01910 instead points to a fieldbus setpoint-timeout question. If you have no confirmed fault code, the G120 won't-start guide separates missing commands from drive faults. For a line-wide stop with no clear drive cause, start with the machine-down guide.

Request onsite F30002 diagnostics

Share the motor, displayed fault and timing relative to the stop. We can discuss an onsite investigation; a code alone cannot guarantee a component replacement or restart.

Request Onsite Service

Or call (920) 851-6363 or email info@westengineeringsystems.com.