Hitachi LPD Series Modules LPD150A

Technical Dossier

Product Details And Specifications

Hitachi LPD Series Technical Notes

The Hitachi LPD Series represents a core family of industrial control and I/O modules deployed extensively across global heavy industry sectors, including petrochemical refineries, nuclear power generation facilities, offshore oil & gas platforms, and large-scale chemical processing plants. These modules form the backbone of Hitachi's distributed control system (DCS) architecture, providing deterministic process control, high-density I/O interfacing, and robust backplane communication in environments where continuous uptime is non-negotiable. Installed base counts for the LPD Series remain significant across Asia-Pacific, the Middle East, and European industrial corridors, making long-term spare parts availability a critical operational concern for plant maintenance engineers and procurement teams worldwide.

The Evolution of LPD Series Architecture

The LPD Series was developed as part of Hitachi's modular DCS platform strategy, designed to interface with the HIDIC and HIZAC control system families. Early-generation LPD modules utilized parallel backplane bus communication with fixed-address slot assignment, requiring manual DIP-switch configuration for node identification. Mid-generation revisions introduced semi-automatic address negotiation and improved EMI shielding to meet IEC 61000-4 industrial immunity standards. Later variants incorporated enhanced diagnostic registers accessible via the system engineering terminal, enabling online fault isolation without process interruption.

Compatibility across LPD generations is constrained by backplane bus revision: modules from different bus generations cannot be mixed within the same rack without an interposer adapter card. Plants operating mixed-generation racks must verify bus revision stamps on the module faceplate before substitution. As the LPD Series has entered its mature-to-end-of-life phase, Hitachi has ceased active production of most variants. Replacement pathways typically involve migration to the Hitachi HIZAC EC or compatible third-party DCS platforms, though the capital cost and process risk of full migration sustains strong demand for original LPD spare parts in the MRO (Maintenance, Repair & Operations) market.

LPD Series Full Catalog & Functionalities (SKU List)

The following catalog covers verified Hitachi LPD Series module part numbers, organized by functional category. Each entry reflects a distinct hardware configuration with unique I/O count, signal type, or communication role.

Power Supply Modules

• LPD150A: 150W DC power supply module for LPD rack; 24VDC input, regulated backplane output
• LPD100A: 100W compact power supply; single-rail backplane feed for low-density racks
• LPD200A: 200W high-capacity power supply; dual-rail output for high-density I/O racks
• LPD151A: Redundant power supply module; hot-swap capable, paired with LPD150A

CPU / Controller Modules

• LPD-CPU01: Main processor module; ladder logic execution, 256KB program memory
• LPD-CPU02: Enhanced CPU with expanded memory (512KB) and faster scan cycle
• LPD-CPUA: Redundant CPU module; synchronous hot-standby operation with automatic failover

Digital Input (DI) Modules

• LPD-DI16A: 16-channel 24VDC digital input; sink/source configurable, 3ms filter
• LPD-DI32A: 32-channel high-density DI; 24VDC, common ground grouping per 16 channels
• LPD-DI16B: 16-channel 120VAC digital input; optically isolated, zero-cross detection

Digital Output (DO) Modules

• LPD-DO16A: 16-channel transistor output; 24VDC, 0.5A per channel, short-circuit protected
• LPD-DO16R: 16-channel relay output; 250VAC/30VDC, 2A per contact, Form-C contacts
• LPD-DO32A: 32-channel high-density transistor output; 24VDC, grouped commons

Analog Input (AI) Modules

• LPD-AI08A: 8-channel analog input; 4–20mA / 0–10V selectable, 12-bit resolution
• LPD-AI08B: 8-channel AI with HART pass-through; supports HART 5/6/7 field devices

Analog Output (AO) Modules

• LPD-AO04A: 4-channel analog output; 4–20mA, 12-bit DAC, loop-powered field devices

Communication / Network Adapter Modules

• LPD-COM01: RS-232C/RS-485 serial communication adapter; Modbus RTU master/slave
• LPD-NET01: Ethernet communication module; 10BASE-T, Modbus TCP, FINS protocol

Quality Control for the LPD Series Range

LPD Series modules present specific test challenges due to their proprietary backplane bus protocol and multi-layer PCB construction. DriveKNMS applies the following inspection and verification procedures to all LPD inventory prior to dispatch: