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FANUC Alarm PRIO-493Modbus Socket Error

FANUC PRIO-493 (“Modbus Socket Error”): The Modbus TCP Server was not able to open and use a TCP network socket. First check: This alarm generally implies that the Ethernet or TCP/IP interface is not set up correctly.

Updated 2026-08-29 · LogrobotLM reference

Description

The Modbus TCP Server was not able to open and use a TCP network socket.

Remedy · Remède

This alarm generally implies that the Ethernet or TCP/IP interface is not set up correctly. For example, if no IP address is defined, then the TCP/IP stack cannot initialize. Verify network connectivity using the ping utility (on the robot, and also on the local PC).

Frequently asked · Questions fréquentes

What does FANUC alarm PRIO-493 mean?
FANUC PRIO-493 (“Modbus Socket Error”): The Modbus TCP Server was not able to open and use a TCP network socket.
How do you troubleshoot FANUC alarm PRIO-493?
This alarm generally implies that the Ethernet or TCP/IP interface is not set up correctly. For example, if no IP address is defined, then the TCP/IP stack cannot initialize. Verify network connectivity using the ping utility (on the robot, and also on the local PC).

Related codes / Codes liés

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 →