Fuji Electric WPLAC Series Modules

Technical Dossier

Product Details And Specifications

Fuji Electric WPLAC Series: Comprehensive Module Range and Technical Overview

The Fuji Electric WPLAC Series represents a core product line within Fuji Electric's programmable logic controller (PLC) and distributed control system (DCS) portfolio. These modules have been deployed extensively across global heavy industries including petrochemical refineries, nuclear power generation facilities, chemical processing plants, and continuous-process manufacturing environments. The WPLAC architecture is engineered for deterministic scan-cycle execution, high-noise-immunity backplane communication, and long-term field reliability under 24/7 operational demands. Installed base spans facilities across Japan, Southeast Asia, the Middle East, and Europe, where Fuji Electric DCS infrastructure remains active in both legacy and hybrid-modernized control architectures.

The Evolution of WPLAC Architecture

The WPLAC Series was introduced as part of Fuji Electric's MICREX-F and MICREX-SX control system generations, targeting mid-to-large scale process automation. Early WPLAC modules operated on a proprietary parallel backplane bus with fixed I/O addressing, requiring manual DIP-switch configuration for slot assignment and interrupt priority. As the series matured, Fuji Electric introduced enhanced variants with onboard diagnostics, expanded memory addressing, and compatibility with the MICREX-SX high-speed serial backplane. The transition from MICREX-F to MICREX-SX introduced breaking changes in backplane pinout and firmware protocol, meaning WPLAC modules are generation-specific and cannot be freely interchanged across chassis families without engineering validation. As of 2026, the WPLAC Series is in the mature-to-end-of-life phase. Fuji Electric has migrated new project designs to the MICREX-SX NP1 and NP3 series. However, the installed base of WPLAC-based systems remains substantial, and replacement modules are required for corrective maintenance, hot-standby redundancy restoration, and scheduled preventive overhaul programs.

WPLAC Full Catalog & Functionalities (SKU List)

The following SKUs represent verified models within the Fuji Electric WPLAC Series, classified by functional category:

CPU & Controller Modules

• WPLAC-30: Main CPU module for MICREX-F mid-range PLC rack; 16KB program memory, RS-232C loader port.
• WPLAC-31: Enhanced CPU with expanded 32KB program memory and extended instruction set support.
• WPLAC-32: High-speed CPU variant with reduced scan cycle time for fast-loop process control.
• WPLAC-33: Redundant CPU module for hot-standby duplex configurations in critical process applications.

Digital Input (DI) Modules

• WPLAC-10: 16-point 24VDC digital input module; sink/source selectable; LED status per channel.
• WPLAC-11: 32-point 24VDC digital input module; high-density I/O for space-constrained rack installations.
• WPLAC-12: 16-point 100/120VAC digital input module for direct field device interfacing.

Digital Output (DO) Modules

• WPLAC-20: 16-point transistor output module; 24VDC, 0.5A per point; short-circuit protected.
• WPLAC-21: 16-point relay output module; 250VAC/30VDC, 2A per point; mechanical relay with LED indication.
• WPLAC-22: 32-point transistor output module; high-density digital output for actuator-dense applications.

Analog Input (AI) Modules

• WPLAC-40: 4-channel analog input; 4–20mA / 0–10V selectable; 12-bit resolution.
• WPLAC-41: 8-channel analog input; 4–20mA; 12-bit resolution; suitable for multi-loop PID control.
• WPLAC-42: 4-channel thermocouple input module; supports J, K, T, E type; cold junction compensation onboard.

Analog Output (AO) Modules

• WPLAC-50: 4-channel analog output; 4–20mA; 12-bit resolution; used for control valve and VFD setpoint signals.
• WPLAC-51: 2-channel analog output; 0–10V; 12-bit; for positioner and proportional actuator control.

Communication & Network Adapter Modules

• WPLAC-60: RS-485 multi-drop communication adapter; supports Modbus RTU protocol for field device integration.
• WPLAC-61: Ethernet communication module; 10BASE-T; for SCADA and HMI data exchange over plant LAN.

Power Supply Modules

• WPLAC-70: 24VDC rack power supply module; 5A output; input range 85–264VAC; DIN rail or rack mount.
• WPLAC-71: Redundant power supply module; hot-swap capable; for uninterrupted rack power in critical installations.

Sourcing Hard-to-Find & Obsolete WPLAC Parts

With the WPLAC Series in end-of-life status, Fuji Electric no longer manufactures new units for the majority of models in this range. OEM lead times for any remaining new-old-stock (NOS) inventory are indeterminate. DriveKNMS maintains a dedicated inventory of WPLAC Series modules sourced through authorized surplus channels, decommissioned plant buybacks, and verified third-party supply networks. All units are catalogued by part number, hardware revision, and firmware version where applicable. DriveKNMS provides lifecycle extension support specifically for facilities that cannot justify a full DCS migration within their current capital expenditure cycle. This includes single-module corrective replacements, multi-module kitting for scheduled turnaround maintenance, and long-term supply agreements for facilities with multi-year maintenance contracts. Customers operating MICREX-F systems with WPLAC backplanes are advised to maintain a minimum strategic spare holding of CPU, power supply, and high-utilization I/O modules to mitigate unplanned downtime risk.

Quality Control for the WPLAC Range

WPLAC Series modules present specific technical challenges during inspection and testing due to their proprietary backplane bus architecture and onboard EEPROM-based configuration storage. DriveKNMS applies a structured multi-stage quality control protocol to all WPLAC units prior to dispatch. Visual inspection covers PCB condition, capacitor integrity, connector pin alignment, and conformal coating status. Functional testing is performed using a Fuji Electric-compatible MICREX-F rack test bench, where each module is powered under rated conditions and exercised through its full I/O channel range. CPU modules are validated for program load/execute cycles, watchdog timer function, and loader port communication. Analog modules are calibrated against a traceable reference standard with channel-by-channel linearity and offset verification. Communication modules are tested for protocol handshake, baud rate stability, and error frame rejection. All test results are documented and accompany each shipment as a module-level test record.