The IDEC FA-2J is a micro/nano PLC from the 1990s–early 2000s era. It is the direct predecessor to the popular MicroSmart series. Its primary claim to fame is being one of the smallest PLCs at its time with a built-in power supply, CPU, I/O, and programmer port in a housing slightly larger than a deck of cards.
Target Audience (Legacy): Machine builders needing simple relay replacement, standalone sequence control, or OEM cost-sensitive applications.
Current Use Case: Only for maintaining existing machinery. Do not use for new designs (discontinued; parts scarce; software obsolete). idec plc fa2j manual
The IDEC FA2J User Manual is a classic example of late-80s/early-90s industrial documentation. It is dense, logic-focused, and functionally comprehensive but lacks the visual polish and intuitive navigation of modern documentation. It serves as a competent reference for seasoned electricians but can be overwhelming for novice programmers due to its "wall of text" approach to instruction set explanations. The IDEC FA-2J is a micro/nano PLC from
If you’re working with the IDEC FA2J series PLC, here’s a concise, practical blog-style overview to help you get up and running and find the right manual. If you’re working with the IDEC FA2J series
| Feature | Specification | |--------|----------------| | CPU Types | FA2J-CPUA (24V DC), FA2J-CPUB (100-240V AC) | | Program Capacity | 3.2k steps (EEPROM) | | I/O Points | Max 120 points (24 built-in + expansion) | | Instruction Set | Basic (27 types) + Advanced (43 types – e.g., MOV, CMP, INC) | | Execution Speed | 2.0 µs / basic instruction | | Timers/Counters | 128 timers (0.01–3276.7 sec), 128 counters (1–32767) | | Internal Relays | 512 points (M0–M511) | | Data Registers | 256 words (D0–D255) |
When the "ERROR" LED blinks on your FA2J CPU, do not panic. Flip to the Diagnostics section of the manual.