What It Is – FX3U Compact PLC
The Mitsubishi FX3U is a compact programmable logic controller (PLC) that gives you flexibility on the input side: it accepts either DC or AC inputs, and the same CPU can be powered from 24 VDC or from mains voltage (115 or 230 VAC). Outputs are available as relay or transistor, depending on the specific model variant within the series. That range of I/O and supply options makes the FX3U a go-to for legacy line retrofits where the cabinet already has mixed-voltage control wiring, or for OEM designs that need to ship one controller into both North American and European plants without changing the BOM.
Lifecycle Reality – Mature, Not Dead
The FX3U is a mature product; firmware updates and expanded features are not expected. Source this against an RFQ; lead times are consistent.
Integrator's Quick Spec Recap
Input: DC Input or AC Input – the PLC can handle either, but you pick a specific model when ordering. Power: choose 24 VDC, 115 VAC, or 230 VAC – not multi-voltage auto-ranging, so confirm your plant voltage before buying. Output: relay for high-current or mixed-voltage loads, transistor for high-speed switching or DC-only circuits. Built-in timers and counters are standard, and the FX3U can be programmed via the front panel or from a PC – handy for on-the-floor edits without firing up a laptop.