Part identification and key ratings
The Mitsubishi FX3U-80MR/DS is a programmable controller with 40 digital inputs and 40 relay outputs, giving 80 I/O points on a single base unit. Power supply is 24 VDC with a tolerance of +20%/-30%, and the unit draws 45 W. Ambient operating range is 0–55 °C.
Comparison with FX2N-80MR-DS
The FX2N-80MR-DS predecessor has the same 40/40 I/O split and relay outputs. Power consumption is 40 W versus 45 W on the FX3U; dimensions are 28.5 × 9 × 8.7 cm versus 28.5 × 9 × 8.6 cm.
Installation notes
Noise immunity is rated at 1000 Vpp with a 1 µs pulse at 30–100 Hz. Maintain good grounding practice and separate power and signal wiring per Mitsubishi guidelines. Relay outputs are rated for general-purpose switching; verify contact ratings for your load.