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ABB Error 34251Rectifier / power supply three-phase fault

Error / Erreur

🇫🇷 Redresseur / Alimentation triphasée

ENTRAÎNEMENT : REDRESSEUR, DC-LINK, BLEEDER, ENERGY BANK (34xxx, 36xxx, 386xx S4C+)

ABB 34251 (“Rectifier / power supply three-phase fault”): Rectifier / power supply three-phase fault — ABB robot hardware event on the rectifier / power supply three-phase (IRC5). Likely part: Redresseur / Alimentation triphasée (rectifier / power supply three-phase).

Updated 2026-08-29 · LogrobotLM reference

What it means · Ce que ça veut dire

Rectifier / power supply three-phase fault — ABB robot hardware event on the rectifier / power supply three-phase (IRC5). Seen across controller generations. Severity: Critical. Field diagnosis below (French); your robot's own manual remains authoritative.

Perte d’une phase secteur détectée par le redresseur.

What to check · Que vérifier

  • Inspect the rectifier / power supply three-phase, its wiring and connections first.
  • Match this code against your robot's event-log timeline before swapping parts.
  • Follow the French field checks below — they are the tested sequence for this fault.
  • Mesurer les trois phases en amont, contrôler interrupteur principal, filtre secteur, fusibles, contacteurs, câblage triphasé et redresseur.
  • À savoir : Erreur physique d’alimentation; peut provoquer ensuite des défauts DC-link et drive.

Part to check / replace · Pièce à contrôler / remplacer

ABB 34251 points to the hardware below — start here before ordering. · 34251 met en cause l'organe ci-dessous : commencez par là.

Tap a part for every code that points to it — and verify the exact variant for your controller before ordering. · Touchez une pièce pour tous les codes qui la citent ; vérifiez la variante exacte avant commande.

Frequently asked · Questions fréquentes

What does ABB error 34251 mean?
ABB 34251 (“Rectifier / power supply three-phase fault”): Rectifier / power supply three-phase fault — ABB robot hardware event on the rectifier / power supply three-phase (IRC5). Seen across controller generations. Severity: Critical. Field diagnosis below (French); your robot's own manual remains authoritative.
How do you troubleshoot ABB error 34251?
Inspect the rectifier / power supply three-phase, its wiring and connections first. Match this code against your robot's event-log timeline before swapping parts. Follow the French field checks below — they are the tested sequence for this fault.
Which part is involved in ABB 34251?
34251 points to Redresseur / Alimentation triphasée (rectifier / power supply three-phase). Confirm the real cause against the robot backup before replacing a part.

Related codes / Codes liés

Same hardware involved / Même matériel en cause

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. · Informations indicatives issues du terrain — le manuel du constructeur et ses procédures de sécurité font foi. Ne shuntez jamais un organe de sécurité ; consignez (LOTO) avant toute intervention physique. How this reference is built →