ObF: alarm during deceleration
The Schneider source associates ObF with too fast braking, dragging load or high power. The choice of correction depends on the process and hardware installed.
The case in 60 seconds
The Schneider source associates ObF with too fast braking, dragging load or high power. The choice of correction depends on the process and hardware installed.
Note if the defect is under arrest and if the load continues to drag the engine.
The code or symptom directs research, but does not show the fault component alone.
Diagnostic map
Follow the rows in order. Each phase must produce evidence before moving to the next.
| Phase | Controls | Evidence to obtain | Next decision |
|---|---|---|---|
| 01Recognize and collect |
| Event context and complete initial data. | If a data is missing, do not reset to attempts: complete the initial picture first. |
| 02Check and separate hypotheses |
| External causes, configuration, circuit and separate process. | If the data does not match, return to the correct schema and revision before changing parameters. |
| 03Interpret and demonstrate |
| Cause supported by repeatable data and authorized evidence. | If the cause is not proven, stop changes and involve manufacturer, OEM or machine manager. |
Reading and observation
Recognize and collect
- Note if the defect is under arrest and if the load continues to drag the engine.
- Collect set ramp and presence of braking accessories without opening the picture.
Event context and complete initial data.
If the result does not matchIf a data is missing, do not reset to attempts: complete the initial picture first.
Qualified technician
Check and separate hypotheses
- Compare the required deceleration with the machine and operating conditions.
- Check the power supply with suitable personnel and equipment, according to the procedure of the site.
External causes, configuration, circuit and separate process.
If the result does not matchIf the data does not match, return to the correct schema and revision before changing parameters.
Specialist deepening
Interpret and demonstrate
- The source contemplates ramp, adaptation of deceleration and braking resistance; are alternatives to measure and verify, not universal values.
- On coordinated compressors and processes, it agrees with changes with OEM constraints and the controller sequence.
Cause supported by repeatable data and authorized evidence.
If the result does not matchIf the cause is not proven, stop changes and involve manufacturer, OEM or machine manager.
What to avoid
- Use repeated resets as a diagnostic test.
- Transfer codes, thresholds or parameters from one Drives family to another.
- Change a protection before connecting symptoms, measurement and phase of the cycle.
- Do not install a resistance or change the stopping behavior without checking the specific size and machine.
When the problem is really solved
Keep the comparison before/after on a representative stop, including time, load and absence of the event.
- The cause is supported by data and not only by the momentary absence of the alarm.
- The cycle that generated the problem has been repeated in authorized conditions.
- Final configuration, measurements and outcome are consistent with applicable machine, drive and documentation.
Applicable documents
Always check size, firmware, options and revision. These sources do not extend the case to other families.
- Primary source of the caseOpen the official source la
- Schneider Electric · Programming and DiagnosticManual · EN · NVE41295 · Official PDF
- Schneider Electric · InstallationManual · EN · NVE41289 · Official PDF