Fuji Electric NP2L Series Modules NP2L-RP1 Electric Repeater Unit

Technical Dossier

Product Details And Specifications

Fuji Electric NP2L Series Technical Notes

The Fuji Electric NP2L series is a relay-based programmable controller platform deployed extensively across global heavy industry sectors, including petrochemical refineries, chemical processing plants, power generation facilities, and continuous-process manufacturing lines. Engineered for deterministic control in high-availability environments, the NP2L platform established a long-term installed base across Asia-Pacific and EMEA industrial sites throughout the 1990s and 2000s. Its modular backplane architecture, standardized I/O addressing, and robust noise immunity made it a preferred choice for plant engineers requiring reliable discrete and analog control without the overhead of full DCS infrastructure. Many NP2L installations remain operational today as embedded control nodes within larger SCADA and DCS hierarchies, driving sustained demand for spare parts, replacement modules, and lifecycle extension support.

The Evolution of NP2L Architecture

The NP2L series emerged from Fuji Electric's NP-series programmable controller lineage, which traces its origins to relay-ladder logic controllers introduced in the early 1980s. The NP2L generation introduced a structured modular backplane, separating CPU, power supply, I/O, and communication functions into discrete plug-in modules — a design philosophy that improved field serviceability and reduced mean time to repair (MTTR) in plant environments.

Early NP2L deployments used proprietary Fuji Electric programming tools and serial communication interfaces. As industrial networking evolved, the platform incorporated RS-232C and RS-485 communication adapters, enabling integration with SCADA systems and HMI panels. The NP2L's instruction set supported relay ladder logic (RLL) and a limited set of function block operations, consistent with IEC 61131-3 precursor standards.

NP2L Full Catalog & Functionalities (SKU List)

CPU & Controller Modules

• NP2L-CPU1: Base CPU module, relay ladder logic, 1K step program memory, RS-232C port
• NP2L-CPU2: Enhanced CPU, 2K step memory, extended instruction set, battery-backed RAM
• NP2L-CPU3: High-capacity CPU, 4K step memory, dual serial ports, real-time clock
• NP2L-CPU4: Advanced CPU with expanded data register capacity and interrupt input support

Digital Input (DI) Modules

• NP2L-X16: 16-point DC 24V digital input module, sink/source compatible
• NP2L-X32: 32-point DC 24V digital input, high-density I/O expansion
• NP2L-XA8: 8-point AC 100/200V digital input module for high-voltage field signals

Digital Output (DO) Modules

• NP2L-Y16R: 16-point relay output module, 2A per point, NO contacts
• NP2L-Y16T: 16-point transistor output, DC 24V, 0.5A per point, sink type
• NP2L-Y32T: 32-point transistor output, high-density discrete control

Analog I/O Modules

• NP2L-AD4: 4-channel analog input, 4–20mA / 0–10V selectable, 12-bit resolution
• NP2L-DA2: 2-channel analog output, 4–20mA / 0–10V, 12-bit DAC
• NP2L-AD8: 8-channel analog input expansion, process signal acquisition

Communication & Network Modules

• NP2L-RS4: RS-485 communication adapter, multi-drop serial network, Modbus RTU support
• NP2L-RS2: RS-232C communication module, point-to-point HMI/SCADA interface

Power Supply Modules

• NP2L-PA1: AC 100/200V input power supply module, DC 24V backplane output, 3A rated
• NP2L-PD1: DC 24V input power supply module for battery-backed or DC-bus installations

Repeater & Extension Modules

• NP2L-RP1: Electric repeater unit for I/O bus extension; extends backplane communication distance between base units; used in distributed rack configurations where physical separation between CPU and remote I/O racks exceeds standard cable limits
• NP2L-EX1: I/O expansion base unit, connects to CPU rack via NP2L-RP1 repeater link

Quality Control for the NP2L Range

NP2L modules present specific testing challenges due to their backplane bus architecture, proprietary communication protocols, and age-related component degradation. DriveKNMS applies a structured multi-stage inspection and functional test protocol to all NP2L units prior to dispatch.