What it means
A49937 (UPS not ready) means that the uninterruptible power supply (UPS) is not ready. The drive outputs the message via the signal source of binector input p6577[25] of the Control Unit — it is only passing on the state of the signal interconnected there, not reporting a fault it has measured itself. Depending on the drive configuration, the same condition can also be issued as fault F49937 instead of as an alarm.
Why it appears
- The uninterruptible power supply (UPS) is not in the ready state.
What to check
- Check the UPS. This is the remedy the manual gives: because the message only mirrors the state of the signal at p6577[25], the UPS itself and its monitoring signal are the things to verify.
Parameters the manual names
- p6577 — BI: Circuit monitoring functions signal source / I_cct mon s_s: the message is reported from index [25] of this signal source, so this is where the UPS signal reaches the Control Unit; check what is interconnected here while troubleshooting.
Acknowledging and restarting
As alarm A49937 the message needs no acknowledgment and triggers no drive reaction; it clears itself once the UPS is ready again. If the condition is configured as fault F49937 instead, the Infeed, SERVO, VECTOR and HLA drive objects react with OFF1 by default (each object can be set to alternative reactions), and the fault must then be acknowledged IMMEDIATELY.
The same on every family
Every manual that describes A49937 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. 3296 |
The drives this code lives on
A49937 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 A49937 mean?
It means "UPS not ready": the uninterruptible power supply (UPS) is not ready. The drive reports this via the signal source of binector input p6577[25] of the Control Unit.
How is A49937 reset?
As an alarm it needs no acknowledgment and causes no drive reaction; it clears itself once the UPS is ready again. If configured as fault F49937 instead, it must be acknowledged IMMEDIATELY.
Can A49937 also appear as a fault?
Yes. Depending on the configuration, the same condition can be issued as F49937; the Infeed, SERVO, VECTOR and HLA drive objects then react with OFF1 by default.
Which parameter belongs to A49937?
p6577, the BI signal source of the circuit monitoring functions — the message is output from index [25] of this signal source.
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