What it means
F30068 (Power unit: undertemperature inverter heat sink) is raised when the drive measures an inverter heat sink temperature below the permissible minimum value. The manuals describe the fault in the same way for SINAMICS G120, G120XA, S120 and S150. The drive coasts down (OFF2) and the fault must be acknowledged immediately before the drive will start again.
Why it appears
- The power unit is being operated at an ambient temperature that lies below its permissible range.
- The temperature sensor evaluation is defective.
What to check
- Check the ambient temperature at the place where the power unit is installed; it must not lie below the range the unit is permitted to operate in.
- Ensure that higher ambient temperatures prevail at the installation site.
- If the fault persists although the ambient temperature is sufficiently high, the temperature sensor evaluation in the power unit is defective and the power unit must be replaced.
Reading the message value
The drive writes the measured heat sink temperature into the fault value, stored in r0949. The manual specifies:
- r0949, interpret decimal: inverter heat sink temperature, given in 0.1 °C.
Parameters the manual names
- r0949 — fault value: read the actual inverter heat sink temperature here; interpret the value as decimal, in 0.1 °C.
Acknowledging and restarting
The fault is acknowledged immediately. Because the drive has coasted down, it does not restart until the fault has been acknowledged. As long as the heat sink temperature remains below the permissible minimum, the fault is raised again after acknowledgment.
What differs between the drive families
Straight from the manuals' own fields — F30068 is not described identically everywhere.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | OFF2 | IMMEDIATELY | Power electronics faulted (5) | Power Module | SINAMICS S120, S150 List Manual · p. 2963 |
| G120 | OFF2 | IMMEDIATELY | Power electronics faulted (5) | — | SINAMICS G120 · p. 916 |
| G120XA | OFF2 | IMMEDIATELY | — | — | SINAMICS G120XA PN converter · p. 1162 |
The drives this code lives on
F30068 is described for G120, G120XA, S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does fault F30068 mean on a SINAMICS drive?
The drive has measured an inverter heat sink temperature below the permissible minimum value. It coasts down (OFF2) and the fault must be acknowledged immediately.
What does the fault value of F30068 tell me?
r0949 holds the inverter heat sink temperature that triggered the fault. Interpret the value as a decimal number; it is given in 0.1 °C.
How do I clear fault F30068?
Ensure that higher ambient temperatures prevail at the installation site, then acknowledge the fault. If it recurs, the temperature sensor evaluation is defective and the power unit must be replaced.
Why does F30068 appear only in cold environments?
The power unit is then being operated at an ambient temperature below its permissible range, which the manual lists as a cause of this fault.
Codes next to this one
Source
Written from Siemens' own List Manuals and operating instructions; every number, designation and parameter on this page is checked against them before publication.
All SINAMICS codes: fault and alarm codes · the F30xxx group · SINAMICS manuals · Siemens manuals