What it means
F07904 is raised when the drive commands the contactor of the external armature short-circuit (ASC) to close and the feedback signal configured in p1235 does not report the state "Closed" — r1239.1 = 1 — within the monitoring time set in p1236. Depending on the drive configuration, the same condition can also be issued as an alarm (A) or with no reaction (N).
Why it appears
- While the contactor was being closed, the feedback signal configured in p1235 did not report "Closed" (r1239.1 = 1) within the monitoring time set in p1236.
What to check
- Check that the contactor feedback signal is correctly connected as configured in p1235.
- Check the logic of the contactor feedback signal: r1239.1 = 1 means "Closed", r1239.1 = 0 means "Open".
- Increase the monitoring time in p1236.
- If required, configure the external armature short-circuit without a contactor feedback signal by setting p1231 = 2.
Parameters the manual names
- p1235 (BI: external armature short-circuit contactor feedback signal) — the input whose state the drive monitors during closing; verify here that the feedback signal is connected and assigned correctly.
- p1236 (monitoring time for the external armature short-circuit contactor feedback signal) — the time within which "Closed" (r1239.1 = 1) must arrive; increase it if the contactor reports slower than expected.
- p1231 (armature short-circuit / DC braking configuration, ASC/DCBRK config) — p1231 = 2 runs the external armature short-circuit without a contactor feedback signal.
Acknowledging and restarting
Acknowledge the fault immediately after the cause has been eliminated; the drive can then be restarted. If the drive is configured to issue this condition as an alarm (A) or without reaction (N), the reaction is NONE and there is nothing to acknowledge.
The same on every family
Every manual that describes F07904 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | OFF2 (NONE) | IMMEDIATELY | Application/technological function faulted (17) | None | SINAMICS S120, S150 List Manual · p. 2877 |
| G130, G150 | OFF2 (NONE) | IMMEDIATELY | Application/technological function faulted (17) | None | SINAMICS G130, G150 List Manual · p. 1606 |
The drives this code lives on
F07904 is described for G130, G150, S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does fault F07904 mean?
The drive closed the contactor of the external armature short-circuit, but the feedback signal configured in p1235 did not report the state "Closed" (r1239.1 = 1) within the monitoring time set in p1236.
How do I fix F07904?
Check the connection and the logic of the contactor feedback signal (p1235, r1239.1), and increase the monitoring time p1236 if the contactor needs longer. Alternatively, set p1231 = 2 to run the external armature short-circuit without a contactor feedback signal, then acknowledge the fault immediately.
Can F07904 also appear as an alarm?
Yes. Depending on the drive configuration, the same condition can also be issued as an alarm (A) or with no reaction (N); in both cases the reaction and acknowledgement are NONE.
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 F07xxx group · SINAMICS manuals · Siemens manuals