What it means
A30077 reports that the internal braking resistor is thermally overloaded and that its use has been inhibited as a result. Depending on how the drive is configured, the drive can also output the same condition with no reaction (N).
Why it appears
- The internal braking resistor is thermally overloaded.
- Because of this thermal overload, the drive has inhibited the use of the internal braking resistor.
What to check
- Reduce the power when generating; this is the power that the internal braking resistor has to absorb.
- When a DC link coupling is present, take the generating power of all the coupled power units into consideration.
- Give the internal braking resistor time to recover thermally; once it has recovered, it is enabled again for further use.
Reading the message value
- The drive enters the alarm value into the message value (%1).
- The alarm value can be read in r2124 and is to be interpreted as a decimal number.
- It is the energy absorbed by the braking resistor, given in Ws.
Parameters the manual names
- r2124 (alarm value): read out here how much energy the braking resistor has absorbed; the value is in Ws and is interpreted as a decimal number.
Acknowledging and restarting
The alarm does not have to be acknowledged: once the internal braking resistor has thermally recovered, the drive enables it again for further use.
The same on every family
Every manual that describes A30077 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | Braking Module faulted (14) | Power Module | SINAMICS S120, S150 List Manual · p. 2966 |
The drives this code lives on
A30077 is described for S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does SINAMICS alarm A30077 mean?
The internal braking resistor is thermally overloaded, and the drive has inhibited its use as a result. The alarm value shows the energy absorbed by the braking resistor in Ws.
How do I clear alarm A30077?
Reduce the power when generating. No acknowledgment is needed; once the internal braking resistor has thermally recovered, it is enabled again for further use.
Where can I read the alarm value of A30077?
In r2124, interpreted as a decimal number. It gives the energy absorbed by the braking resistor in Ws.
What does a DC link coupling mean for A30077?
With a DC link coupling, the generating power of all the coupled power units must be taken into consideration when assessing the load on the internal braking resistor.
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 A30xxx group · SINAMICS manuals · Siemens manuals