HITACHI LPD Series Modules: LPD200A

Technical Dossier

Product Details And Specifications

HITACHI LPD Series: Comprehensive Module Range and Technical Overview

The HITACHI LPD Series represents a core family of programmable logic controller (PLC) I/O modules deployed extensively across global heavy industry verticals, including petrochemical refineries, nuclear power generation facilities, chemical processing plants, and continuous-process manufacturing environments. Engineered under HITACHI's industrial automation division, LPD Series modules were designed to interface directly with HITACHI's H-series and EH-series PLC backplane architectures, providing deterministic digital output control in safety-critical and high-availability applications. Installed base records indicate significant deployment across Asia-Pacific, Middle East, and European industrial infrastructure, where long equipment lifecycles of 15–25 years make spare parts availability a persistent operational requirement.

The Evolution of LPD Series Architecture

The LPD Series was introduced as part of HITACHI's modular PLC expansion strategy during the late 1980s and matured through the 1990s alongside the EH-150 and EH-300 controller platforms. Early LPD modules utilized parallel backplane communication with fixed-address slot assignment, requiring manual DIP-switch configuration for I/O mapping. Mid-generation revisions introduced improved optical isolation on output channels, raising common-mode rejection and reducing susceptibility to ground loop interference in high-noise industrial environments.

By the early 2000s, HITACHI transitioned its primary development focus toward the EH-A and EHV series platforms, placing the LPD family into a maintenance-only lifecycle phase. Compatibility constraints are a known integration challenge: LPD modules are electrically and mechanically specific to their designated backplane generations and are not hot-swap compatible with newer HITACHI EH-ETH or EH-OB series racks without adapter hardware. Engineers maintaining legacy LPD-based systems must account for firmware version alignment between the CPU module and I/O expansion racks to avoid address mapping conflicts.

LPD Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified models within the HITACHI LPD Series. Each entry reflects a distinct functional role within the PLC I/O architecture:

LPD200A: Digital output module, 16-point, transistor sink type, 24VDC load
LPD201A: Digital output module, 16-point, transistor source type, 24VDC load
LPD202A: Digital output module, 32-point, transistor sink type, high-density I/O expansion
LPD203A: Digital output module, 32-point, transistor source type, 24VDC
LPD100A: Digital input module, 16-point, 24VDC DC input, sink/source compatible
LPD101A: Digital input module, 32-point, 24VDC, high-density configuration
LPD102A: Digital input module, 16-point, 100–120VAC input, isolated
LPD103A: Digital input module, 16-point, 200–240VAC input, isolated
LPD300A: Relay output module, 16-point, Form A contacts, 250VAC/2A per point
LPD301A: Relay output module, 8-point, Form C contacts, 250VAC/2A, mixed load
LPD400A: Analog input module, 4-channel, 4–20mA / 0–10V selectable
LPD401A: Analog input module, 8-channel, 12-bit resolution, 4–20mA
LPD402A: Analog output module, 4-channel, 4–20mA / 0–10V, 12-bit DAC
LPD500A: Communication adapter module, RS-232C/RS-485, HITACHI proprietary protocol
LPD501A: Communication adapter module, RS-485 multi-drop, Modbus RTU support
LPD600A: Power supply module, 24VDC input, rack-mount, 5A rated output for I/O bus
LPD601A: Power supply module, 100–240VAC input, universal voltage, 5A I/O bus output
LPD700A: Interrupt input module, 8-point, high-speed event capture, 0.1ms response

Sourcing Hard-to-Find & Obsolete LPD Series Parts

The HITACHI LPD Series has been in end-of-life (EOL) status with the OEM for over a decade. New production units are no longer available through standard HITACHI distribution channels. DriveKNMS maintains a dedicated inventory program for LPD Series modules, sourcing verified surplus, refurbished, and new-old-stock (NOS) units from decommissioned plant equipment and authorized secondary market channels.

For operators running LPD-based control systems beyond their original design life, DriveKNMS provides lifecycle extension support including: cross-reference analysis to identify functional equivalents within HITACHI's current EH-A/EHV product lines, compatibility assessment for mixed-generation rack configurations, and long-term consignment stocking agreements for facilities requiring guaranteed spare parts availability over multi-year maintenance contracts. All sourced LPD modules are traceable to documented equipment histories where available.

Quality Control for the LPD Series Range

LPD Series modules present specific test challenges due to their backplane-dependent communication architecture and age-related component degradation patterns. DriveKNMS applies a structured inspection and functional verification protocol to all LPD units prior to dispatch:

Visual inspection covers PCB condition, relay contact wear (for LPD300/301A), capacitor ESR measurement, and connector pin integrity assessment. Functional testing is performed using HITACHI-compatible rack test fixtures that replicate the original backplane bus signaling environment, verifying correct I/O point addressing, output switching response times, and isolation resistance between channels. Analog modules (LPD400/401/402A) undergo calibration verification against traceable reference standards. Communication modules (LPD500/501A) are tested for protocol handshake integrity and baud rate stability across the full specified range. All units that pass functional verification are issued a DriveKNMS inspection certificate with test date and technician reference.