LogrobotLM

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FANUC Alarm SRVO-454 — CPU BUS failure

Error
Hardware
servo amplifier
Controllers
R-30iB (this generation only)
FANUC class
SERVO (default, not tabulated in the sources)
Hardware family
FANUC servo amplifier alarms: power, DC link, currents and IPM

FANUC SRVO-454 (“CPU BUS failure”): Error detected in the data on the internal CPU bus of the amplifier.

Updated 2026-10-22 · LogrobotLM reference

What it means

Error detected in the data on the internal CPU bus of the amplifier.

What to check

  • Replace the amplifier.
  • Note: R-30iB code only.

Related codes

SRVO-451Internal S-BUS failSRVO-455CPU watch dogSRVO-452ROM data failureSRVO-453Low volt driverSRVO-456Ground fault

Indicative field information — the robot manufacturer's manual and safety procedures always prevail. Never bypass a safety device; apply lockout/tagout (LOTO) before any physical intervention. How this reference is built →