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ABB Error 90208 — Chain switch open

Error

ABB 90208 (“Chain switch open”): Chain switch open: a safety chain other than the automatic stop (AS) and the general stop (GS) has been interrupted. Likely part: Chaîne de sécurité auxiliaire / LED run chain (safety chain auxiliaire / LED run chain).

Updated 2026-10-22 · LogrobotLM reference

What it means

Chain switch open: a safety chain other than the automatic stop (AS) and the general stop (GS) has been interrupted.

What to check

  • Read the state of the run chain LEDs on the cabinet LED panel to identify the open loop.
  • Check the devices of the chain concerned (superior stop, limit switch, auxiliary chains) and their wiring.
  • Note: Completes the 9020x block: 90203 enabling device, 90205 AS, 90206 GS, 90208 = "all the others". Recorded in production on IRC5P (painting).

Part to check / replace

ABB 90208 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

90200Limit switch opened by SC90201Limit switch open90202Emergency stop open

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 →