LogrobotLM

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FANUC Alarm PNT1-120 — Pulse coder position compare error

FANUC PNT1-120 (“Pulse coder position compare error”): This alarm is echoed to the PLC when a SRVO-071 SERVO SPHAL alarm (Grp:… Ax:…) alarm is posted. First check: Refer to the SRVO-071 alarm for the remedy.

Updated 2026-09-17 · LogrobotLM reference

Description

This alarm is echoed to the PLC when a SRVO-071 SERVO SPHAL alarm (Grp:… Ax:…) alarm is posted. Refer to the teach pendant alarm screen for further information on the SRVO-071 alarm. Refer to the SRVO-071 alarm for the cause.

Remedy

Refer to the SRVO-071 alarm for the remedy.

Related codes

PNT1-118Motor overheat occurredPNT1-119Pulse coder communication errorPNT1-121Collision Detection (Hand Broke)PNT1-122TP disabled during Test Cycle

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 →