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FANUC Alarm SRVO-242 — SERVO Chain 1 (EXEMG) abnormal

FANUC SRVO-242 (“SERVO Chain 1 (EXEMG) abnormal”): A single chain 1 (+24V) failure occurred when External Emergency stop input was asserted. First check: 1. Repair the circuit of the chain 1 (+24V) on the External Emergency stop hardware.

Updated 2026-09-17 · LogrobotLM reference

Description

A single chain 1 (+24V) failure occurred when External Emergency stop input was asserted.

Remedy

1. Repair the circuit of the chain 1 (+24V) on the External Emergency stop hardware. 2. Set CHAIN FAILURE detection to TRUE on SYSTEM/CONFIG the screen. 3. Press RESET on the teach pendant.

Related codes

SRVO-240SERVO Chain 1 (FENCE) abnormalSRVO-241SERVO Chain 2 (FENCE) abnormalSRVO-243SERVO Chain 2 (EXEMG) abnormalSRVO-244SERVO Chain 1 abnormal(Rbt:…)

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 →