What does FANUC alarm ARC-121 mean?

FANUC ARC-121 (“Weld not performed(Sim mode)”): Simulation mode is enabled. Actual welding is not performed.

FANUC Alarm ARC-121 — Weld not performed(Sim mode)

FANUC ARC-121 (“Weld not performed(Sim mode)”): Simulation mode is enabled. First check: None.

Updated 2026-08-29 · LogrobotLM reference

Description

Simulation mode is enabled. Actual welding is not performed.

Remedy · Remède

None.

Frequently asked · Questions fréquentes

What does FANUC alarm ARC-121 mean?: FANUC ARC-121 (“Weld not performed(Sim mode)”): Simulation mode is enabled. Actual welding is not performed.
How do you troubleshoot FANUC alarm ARC-121?: None.

Related codes / Codes liés

ARC-107STOPL Roboweld internal Error(%d)ARC-120Enable/Disable Sim mode failed ARC-122Cannot SIM/UNSIM(%s,Id:%d)ARC-123Memory size is too small

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