Siemens alarm 611U-F616: DC link undervoltage
SIMODRIVE 611U drive alarm · SIMODRIVE 611D/611U
What it means
The DC link fell below permissible minimum P1162 because the upstream infeed went to a fault state or its supply collapsed. On UI-type infeed installations an overloaded pulsed resistor produces exactly this pattern during heavy braking.
Likely causes
- line supply missing/phasing down at the infeed
- infeed tripped internally (see infeed LED panel)
- pulsed resistor overloaded or its thermal contact open
- precharge/contactor chain dropping the bus under load
Triage note: Acknowledgement is RESET FAULT MEMORY; if it recurs under acceleration spikes, profile the bus voltage before swapping modules.
Replacement parts
We supply the following units for this alarm — tested, warranty-backed:
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6SN1145-… / 6SN1146-…
infeed · Common cause
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pulsed resistor 6SN1113-…
infeed · Common cause
Need the part urgently?
Send us alarm 611U-F616 with your machine details — typical RFQ turnaround is 24–48h.