Siemens SINAMICS V20 VFD
Siemens SINAMICS V20 VFD code A912: Vdc_min controller active
The minimum voltage controller has activated because the direct current link voltage fell below the specified limit during operation.
- Code
- A912
- Name
- Vdc_min controller active
- Controller
- Siemens SINAMICS V20 VFD
- Type
- Low voltage
- What it does
- Warning: the equipment keeps running and flags a problem
- Risk
- GREEN In your wheelhouse
- Reset
- Clears on its own when the condition goes away
- Source
- The manufacturer's manual (subscribers see which manual and page)
Updated November 4, 2026
How to fix it
Subscribers get:
- What to do next, in plain words
- Which manufacturer manual it comes from, linked
- The 3 common causes listed for this code
- The step by step check for this problem, one check at a time
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Questions about this code
What does Siemens SINAMICS V20 VFD code A912 mean?
The minimum voltage controller has activated because the direct current link voltage fell below the specified limit during operation.
Is Siemens SINAMICS V20 VFD code A912 dangerous?
It is graded green: in a working tech's wheelhouse with standard tools and low risk.
How do I fix Siemens SINAMICS V20 VFD code A912?
The manual's fix and the step by step check for this code are in WERCS Diagnose, plans from $49 a month. For help right now, WERCS answers 24/7 at (877) 489-3727.
Other Siemens SINAMICS V20 VFD codes
A541 · Motor data identification activeA600 · RTOS overrun warningA910 · Vdc_max controller deactivatedA911 · Vdc_max controller activeA921 · Analog output parameters not set properlA922 · No load applied to converterA923 · Both JOG left and JOG right are requesteA930 · Cavitation protection warnA936 · PID autotuning activeA952 · Load monitoring warning