Mitsubishi FX0N Series Modules – FXON-16EYT

Technical Dossier

Product Details And Specifications

Mitsubishi FX0N Series Technical Notes

The Mitsubishi Electric FX0N series is a compact, fixed-configuration programmable logic controller (PLC) platform that has maintained a significant installed base across global heavy industry since its introduction in the early 1990s. Deployed extensively in chemical processing plants, petrochemical refineries, water treatment facilities, automotive assembly lines, and building automation systems, the FX0N occupies the entry-to-mid tier of Mitsubishi's FX-family architecture. Its combination of onboard I/O, expandable extension modules, and RS-422 programming port made it a cost-effective control node for standalone machine control and small-scale distributed automation. Units such as the FXON-16EYT — a 16-point transistor (sink) digital output extension module — remain in active service at facilities that have not yet migrated to the FX3U/FX5U generation, making lifecycle support and spare parts availability a critical operational concern.

The Evolution of FX0N Architecture

The FX0N series was introduced by Mitsubishi Electric as a successor to the FX0 platform, retaining the same compact DIN-rail form factor while expanding the maximum I/O count and adding support for special function modules. The base CPU units (FX0N-30MR, FX0N-40MR, FX0N-60MR) integrated onboard relay outputs and 24 VDC transistor variants, communicating with extension blocks via a proprietary high-speed parallel bus. This bus architecture is electrically incompatible with the later FX1N and FX2N series, meaning FX0N extension modules — including digital I/O blocks, analog modules, and communication adapters — cannot be interchanged with newer FX-family hardware without a full system redesign.

By the mid-2000s, Mitsubishi Electric had transitioned its primary development focus to the FX1N and FX2N platforms, and the FX0N was subsequently classified as a mature/end-of-life product line. Official production of many FX0N CPU and extension modules has ceased, though Mitsubishi's authorized service network continues to provide limited repair support. For facilities operating FX0N-based systems beyond their original design life, third-party spare parts suppliers and refurbished module inventories represent the primary sourcing channel for unplanned maintenance events.

FX0N Full Catalog & Functionalities (SKU List)

CPU / Main Units

• FX0N-30MR-ES/UL: 16 DI / 14 DO relay output CPU, 100–240 VAC power supply, 2,000-step program memory.
• FX0N-30MT-ESS/UL: 16 DI / 14 DO transistor sink output CPU, 24 VDC supply, high-speed pulse output capable.
• FX0N-40MR-ES/UL: 24 DI / 16 DO relay output CPU, expanded onboard I/O for mid-scale machine control.
• FX0N-40MT-ESS/UL: 24 DI / 16 DO transistor sink output CPU, 24 VDC, supports 2-axis pulse positioning.
• FX0N-60MR-ES/UL: 36 DI / 24 DO relay output CPU, maximum onboard I/O configuration in the FX0N CPU range.
• FX0N-60MT-ESS/UL: 36 DI / 24 DO transistor sink output CPU, highest-density FX0N base unit.

Digital Input Extension Modules

• FXON-8EX: 8-point 24 VDC digital input extension block, sink/source compatible.
• FXON-16EX: 16-point 24 VDC digital input extension block, standard DIN-rail mount.

Digital Output Extension Modules

• FXON-8EYR: 8-point relay output extension module, 250 VAC / 30 VDC, 2 A per point.
• FXON-8EYT: 8-point transistor sink output extension module, 5–30 VDC, 0.5 A per point.
• FXON-16EYR: 16-point relay output extension module, general-purpose switching loads.
• FXON-16EYT: 16-point transistor (NPN sink) output extension module, 5–30 VDC, 0.5 A per point, suitable for high-frequency switching and solid-state load control.

Mixed I/O Extension Modules

• FXON-8ER: 4 DI / 4 DO relay output combined extension block.
• FXON-8ET: 4 DI / 4 DO transistor output combined extension block.

Analog Modules

• FX0N-3A: 2-channel analog input (0–10 V / 4–20 mA) + 1-channel analog output, 8-bit resolution, connects via FX0N extension bus.

Communication & Special Function Modules

• FX0N-232ADP: RS-232C communication adapter for HMI and barcode scanner interfacing.
• FX0N-422ADP: RS-422 multi-drop communication adapter, supports Mitsubishi computer link protocol.
• FX0N-485ADP: RS-485 adapter enabling Modbus RTU and Mitsubishi N:N network configurations.

Quality Control for the FX0N Range

FX0N extension modules present specific test challenges due to their proprietary parallel bus interface and the age-related degradation common in units that have accumulated 10–20 years of service. DriveKNMS applies the following verification protocol to all FX0N modules prior to dispatch:

• Bus connector inspection: Physical examination of the edge connector pins for oxidation, mechanical deformation, and contact resistance measurement.
• Functional I/O test: Each digital output point on modules such as the FXON-16EYT is individually energized and verified against a calibrated load bank. Relay modules are cycled a minimum of 50 times per output point.
• CPU communication test: Extension modules are connected to a reference FX0N CPU and polled via GX Developer to confirm correct I/O mapping and absence of bus errors.
• Thermal soak: Units are operated at rated load for a minimum of 2 hours at ambient temperature to screen for latent component failures.
• Firmware / parameter retention: CPU units are verified for intact program memory and battery-backed data register retention where applicable.