F30005 Power Unit Overtemperature
In system: Siemens S120 Error Codes
The power module exceeded allowable temperature limits.
Technical Details
Possible Causes
1Cooling fan malfunction
HIGH likelihoodValidate this cause with diagnostic values and wiring/mechanical inspection before replacing parts.
2Blocked ventilation path
MEDIUM likelihoodValidate this cause with diagnostic values and wiring/mechanical inspection before replacing parts.
3Ambient temperature too high
MEDIUM likelihoodValidate this cause with diagnostic values and wiring/mechanical inspection before replacing parts.
Step-by-Step Solution
Action 1
Inspect fan operation and airflow
Details
- Record measured values before and after this action
Action 2
Clean heat sink and vents
Details
- Record measured values before and after this action
Action 3
Reduce load and verify cabinet temperature
Details
- Record measured values before and after this action
Action 4
Check fan status
Details
- Record measured values before and after this action
Action 5
Verify thermal sensor reading
Details
- Record measured values before and after this action
Diagnostic Parameters
| Parameter | Description | Value/Unit |
|---|---|---|
| r0068 | Power unit temperature | deg C |
| r0949 | Fault value | Code-specific |
Prevention Tips
Record baseline operating values after commissioning and compare during maintenance.
Review wiring torque, grounding, and cabinet conditions during planned shutdown.
Apply parameter change control to reduce repeat faults after service activities.