Siemens · DCM
The rectifier component within the power unit has overheated beyond its permissible temperature limit. Potential causes include insufficient cooling (fan failure), excessive motor load, high ambient temperatures, or a failure in one of the line supply phases. Prolonged overtemperature can lead to rectifier failure and drive malfunction.
Click steps to track your progress.
De-energize the drive and inspect any dedicated cooling fans for the rectifier section for proper operation and cleanliness.
Measure the AC input line voltages (L1-L2, L2-L3, L3-L1) at the drive's input terminals to verify balance and stability.
Check for excessive current harmonics on the input supply using a power quality analyzer (e.g., for THDi if available).
Monitor the drive's DC link voltage (e.g., Parameter P2-07) and output current (P2-01) under varying load conditions.
Verify that the drive's output current (P2-01) does not consistently exceed the drive's continuous current rating (e.g., check P1-03).