Fuji Electric NP1B Series Modules: NP1BS-06 Base Board

Technical Dossier

Product Details And Specifications

Fuji Electric NP1B Series: Comprehensive Module Range and Technical Overview

The Fuji Electric NP1B series — marketed under the MICREX-F platform — represents one of the most widely deployed modular PLC architectures in Asia-Pacific heavy industry. Installed across petrochemical complexes, nuclear auxiliary systems, steel rolling mills, and large-scale water treatment facilities, the NP1B backplane and its associated I/O and CPU modules have accumulated decades of field runtime in safety-critical environments. The series is characterized by a passive backplane architecture (base board) onto which CPU, I/O, communication, and power supply modules are inserted, enabling high-density control in compact panel footprints. The NP1BS-06 is a 6-slot base board that serves as the physical and electrical backbone of a single NP1B rack assembly, providing the inter-module bus, power distribution rails, and slot addressing logic for all inserted modules.

The Evolution of NP1B Architecture

Fuji Electric introduced the MICREX-F / NP1 platform in the late 1980s as a successor to its earlier relay-logic and first-generation PLC systems. The NP1B designation identifies the base-board sub-family within the broader NP1 rack system. Early iterations used a proprietary parallel backplane bus operating at TTL logic levels, with slot counts of 4, 6, 8, and 12 positions (NP1BS-04, NP1BS-06, NP1BS-08, NP1BS-12). Through the 1990s, Fuji introduced enhanced CPU modules (NP1L-CPU series) with expanded program memory and floating-point support, while the base board hardware remained backward-compatible — a deliberate design choice that extended the installed base lifecycle well into the 2000s. By the mid-2000s, Fuji Electric began transitioning customers toward the MICREX-SX (SPH series) platform, which introduced a high-speed serial backplane and IEC 61131-3 programming compliance. As of 2026, the NP1B series is classified as End-of-Life (EOL) by Fuji Electric Japan; no new production orders are accepted. However, the installed base remains active in facilities where full DCS migration is cost-prohibitive, making third-party spare parts sourcing and lifecycle extension services the primary support pathway.

NP1B Full Catalog & Functionalities (SKU List)

Base Boards (Backplane)

• NP1BS-04: 4-slot passive base board; minimum rack configuration for compact panels.
• NP1BS-06: 6-slot passive base board; standard mid-density rack; most common field unit.
• NP1BS-08: 8-slot passive base board; high-density I/O expansion rack.
• NP1BS-12: 12-slot passive base board; maximum slot count for large process stations.

CPU Modules

• NP1L-RS1: Basic CPU module; 8K step program memory; RS-232C port.
• NP1L-RS3: Enhanced CPU; 32K step memory; dual RS-232C/RS-485 ports.
• NP1L-CPU11: High-performance CPU; 64K step; supports floating-point arithmetic.
• NP1L-CPU21: Advanced CPU with Ethernet port; supports MODBUS TCP.

Digital Input (DI) Modules

• NP1X-16D: 16-point DC 24V digital input module; sink/source selectable.
• NP1X-32D: 32-point DC 24V digital input; high-density field wiring.
• NP1X-16A: 16-point AC 100/200V digital input module.

Digital Output (DO) Modules

• NP1Y-16T: 16-point transistor output; DC 24V; 0.5A per point.
• NP1Y-16R: 16-point relay output; 2A per point; AC/DC load compatible.
• NP1Y-32T: 32-point transistor output; high-density; common source.

Analog I/O Modules

• NP1AD-04: 4-channel analog input; 4–20 mA / 0–10V; 12-bit resolution.
• NP1DA-02: 2-channel analog output; 4–20 mA; 12-bit DAC.

Communication & Special Modules

• NP1L-RS4: RS-485 multi-drop communication module; MODBUS RTU master/slave.
• NP1L-ET1: Ethernet communication adapter; 10BASE-T; MODBUS TCP.

Power Supply Modules

• NP1PS-24: DC 24V input power supply module; 5A output to backplane bus.
• NP1PS-AC: AC 100–240V input power supply; integrated surge protection.

Sourcing Hard-to-Find & Obsolete NP1B Parts

With Fuji Electric having formally discontinued the NP1B series, procurement teams at chemical plants, power utilities, and municipal water authorities face a narrowing supply window. DriveKNMS maintains a dedicated inventory of NP1B series modules — including base boards such as the NP1BS-06 — sourced through authorized surplus channels, factory-decommissioned equipment, and controlled refurbishment programs. All units are stored in ESD-safe, climate-controlled warehousing. For facilities operating under long-term maintenance contracts (LTMA) or asset integrity programs, DriveKNMS can provide scheduled delivery agreements to ensure continuity of spare parts availability through planned shutdown cycles. Emergency same-day quotation is available for critical production environments.

Quality Control for the NP1B Range

The NP1B base board (NP1BS-06 and related variants) presents specific test challenges due to its passive backplane design: the board itself carries no active logic, but its bus traces, slot connectors, and power rails must meet precise impedance and continuity specifications to ensure reliable inter-module communication. DriveKNMS applies a structured test protocol to all NP1B units: (1) visual inspection of PCB traces, connector pins, and solder joints under 10× magnification; (2) continuity and isolation testing of all backplane bus lines using a 4-wire Kelvin measurement method; (3) functional validation by inserting a known-good CPU and I/O module set and executing a cyclic scan test under rated load; (4) burn-in at 40°C ambient for 24 hours to screen latent component failures. CPU and I/O modules undergo additional firmware version verification and I/O point-level functional testing before release.