This FX3U-16MT/DSS is a MELSEC-F series base unit with 8 integrated digital inputs and 8 transistor source outputs, running on a 24 VDC supply. Program memory is 64K steps in RAM, backed by a buffer battery. The unit is expandable to 256 local I/O points or 384 local plus remote I/O. Cycle time for a basic LD instruction is 65 ns, and for MOV is 642 ns, making it suitable for high-speed sequence control. The USB port is optional; an RS-422 port is standard for programming and networking. Power consumption is 25 W, ambient temperature range 0 to 55 °C, enclosure protection IP10.
This FX3U-16MT/DSS is in the mature stage of its lifecycle. It remains available through standard distribution; lead time is estimated at 1–10 working days. Sourcing is confirmed via RFQ, and the part can be specified into existing BOM lines without obsolescence concerns. For new system designs, Mitsubishi's iQ-F series (e.g., FX5U) offers a more current platform, but the FX3U retains full production support for legacy applications.
Panel Integration
Expansion modules connect via the right-side bus; the RS-422 port allows a programming panel or connection to a MELSEC network. The transistor outputs are source type (PNP), so wiring must match common positive configuration.