What it means
A49920 is the alarm that reports the protective breaker in the main circuit of the power supply has tripped. The message is not produced by a measurement inside the converter itself: it reaches the Control Unit through the signal source of binector input p6577[1] (circuit monitoring functions), so the alarm mirrors the state of that protective breaker. As an alarm, it signals the condition without any automatic drive response; depending on how the drive is configured, the same condition can also be issued as a fault.
Why it appears
- The protective breaker in the main circuit of the power supply has tripped.
What to check
- Check the main circuit of the power supply — the circuit whose protective breaker has tripped.
Parameters the manual names
- p6577 (BI: Circuit monitoring functions signal source) — the signal source this message is output through: the Control Unit receives the protective-breaker status of the main circuit via the binector input p6577[1].
Acknowledging and restarting
As an alarm, A49920 does not require an acknowledgment — deal with the tripped protective breaker in the main circuit of the power supply. If the drive configuration issues the same condition as a fault, the drive object is switched off (OFF1 is the default reaction; the manual lists alternative reactions per drive object) and the fault must be acknowledged IMMEDIATELY before the drive will run again.
The same on every family
Every manual that describes A49920 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | General drive fault (19) | None | SINAMICS S120, S150 List Manual · p. 3292 |
The drives this code lives on
A49920 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 A49920 mean?
It reports that the protective breaker in the main circuit of the power supply has tripped. The signal reaches the Control Unit through the binector input p6577[1] of the circuit monitoring functions.
How do I clear A49920 on SINAMICS S120 or S150?
Check the main circuit of the power supply and remedy the tripped protective breaker. The alarm itself needs no acknowledgment; if the condition is configured as a fault, it must be acknowledged IMMEDIATELY.
Does A49920 stop the drive?
As an alarm, no — it signals the condition without switching the drive off. If the drive configuration raises the same condition as a fault, the drive object is switched off (OFF1 is the default) and the fault must be acknowledged IMMEDIATELY.
Which parameter belongs to A49920?
p6577, the binector input signal source of the circuit monitoring functions. The message is output via the signal source of binector input p6577[1].
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 A49xxx group · SINAMICS manuals · Siemens manuals