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ABB Error 38644 — DC-link / cable motor / Isolation fault

Error

ABB 38644 (“DC-link / cable motor / Isolation fault”): Voltage fault associated with the DC link, which can be triggered by an insulation failure in a motor cable or an anomaly in the DC distribution. Likely part: DC-Link / Câble moteur / Isolation (DC-link / cable motor / Isolation).

Updated 2026-10-22 · LogrobotLM reference

What it means

Voltage fault associated with the DC link, which can be triggered by an insulation failure in a motor cable or an anomaly in the DC distribution.

What to check

  • LOTO.
  • Check the motor cable insulation, the power connections and the DC busbar; correlate with 38600 and the affected axes before replacing hardware.
  • Note: S4C+ code often encountered together with 38600; the field cause can be insulation degradation of the motor wiring.

Part to check / replace

ABB 38644 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 →