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ABB Error 34266 — Rectifier / Drive Unit fault

Error

ABB 34266 (“Rectifier / Drive Unit fault”): Inrush current limiting resistor and discharge resistor active simultaneously; abnormal state of the power circuit. Likely part: Rectifier / drive unit.

Updated 2026-10-22 · LogrobotLM reference

What it means

Inrush current limiting resistor and discharge resistor active simultaneously; abnormal state of the power circuit.

What to check

  • Check the mains voltage, the transformer voltage selection if present, the discharge resistor and the wiring; replace the unit if the fault persists.
  • Note: Power circuit/rectifier fault; not to be confused with a simple motor fault.

Part to check / replace

ABB 34266 points to the hardware below — start here before ordering.

Tap a part for every code that points to it — and verify the exact variant for your controller before ordering.

Related codes

34100Drive system fault34200Axis Computer / Drive Units fault34201Drive Unit 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 →