Analog input board for FX3G/FX3S PLCs
The Mitsubishi FX3G-2AD-BD is a 2-channel analog input expansion board that mounts directly onto FX3G or FX3S series PLCs, adding two mixed-use voltage or current inputs without consuming any I/O points. Each channel accepts either 0–10 VDC (input resistance 198.7 kΩ) or 4–20 mA current, with 12-bit binary digital output and a conversion time of 180 µs per channel — fast enough for process monitoring on a compact machine controller. Accuracy at 25 °C is ±0.5% of full scale (10 V or 16 mA), widening to ±1.0% across the 0–55 °C operating range. Resolution on the voltage input is 2.5 mV per count.
Compatibility and constraints
Requires FX3G firmware V1.10 or later. When used with an FX3S base unit, the FX3S-CNV-ADP adapter cannot be installed simultaneously — the board occupies the same expansion slot. The analog inputs are non-isolated from the PLC main unit — no isolation between channels or between input and logic. Do not perform dielectric or insulation resistance tests on the analog terminals; the board is not designed to withstand them. Rated for operation at altitudes up to 2,000 m; above that, pressurized environments may cause failure. Ambient temperature range is 0–55 °C operating, -20–70 °C storage, with 5–95% RH non-condensing.
Vibration resistance: 10–57 Hz at 0.075 mm half-amplitude (direct mount) or 0.035 mm (DIN rail mount), and 57–150 Hz at 9.8 m/s², 10 sweeps per axis. Shock: 147 m/s² half-sine, 11 ms duration, 3 times per axis. Noise immunity tested to 1,000 Vp-p, 1 µs width, 1 ns rise time, 30–100 Hz repetition — suitable for industrial panel environments with typical switching noise. Atmosphere must be free of corrosive or flammable gases and conductive dust. Not rated for outdoor or washdown use.
No official successor has been announced. The FX3G-2AD-BD remains the direct analog input solution for FX3G and FX3S platforms.