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ABB Error 39427 — Rectifier communication missing

Error

ABB 39427 (“Rectifier communication missing”): Rectifier communication missing: communication with the rectifier on the drive unit communication link is lost. Likely part: Rectifier / drive communication link.

Updated 2026-10-22 · LogrobotLM reference

What it means

Rectifier communication missing: communication with the rectifier on the drive unit communication link is lost. No operation is possible until it is corrected.

What to check

  • Check the rectifier power supply and the continuity of the communication link to the drive units.
  • Check the connection and condition of the signal cable.
  • Check that the rectifier is actually supplied by the mains (see 34252).
  • Restart the cabinet; replace the rectifier if the link is not restored.
  • Note: Often occurs in a cascade with 39426 and 39428: address the signal link only once for all three.

Part to check / replace

ABB 39427 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

32540Drive unit / firmware fault32541Drive unit / firmware fault39008Drive units 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 →