A410.00 to A410.15

CPU Bus Unit Number Duplication

Omron · SYSMAC CJ2 CPU Unit

What does A410.00 to A410.15 mean?

This flag turns ON when a CPU Bus Unit's unit number has been duplicated. Bits 00 to 15 correspond to unit numbers 0 to F. The Duplication Error Flag (A401.13) will also turn ON. The CPU Unit operation will stop, and the ERR/ALM indicator on the front of the CPU Unit will light.

Common Causes

  • Two or more CPU Bus Units are configured with the same unit number (0 to F)
  • Incorrect physical DIP switch settings on the CPU Bus Units lead to duplicated addresses

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Identify the problematic CPU Bus Unit(s) by checking the ON status of A410.00 to A410.15 (Bits 00-15 for Unit numbers 0-F)

  2. 2

    Physically inspect the DIP switch settings on all CPU Bus Units to verify unique unit numbers

  3. 3

    Access the PLC Setup or I/O Table in CX-Programmer to review the configured unit numbers for all CPU Bus Units

  4. 4

    Reconfigure either the physical DIP switches or the software settings to ensure each CPU Bus Unit has a unique unit number

Browse all codes in this manual (27)
Verified technical data. Last updated: March 2026

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