Harland Simon H4890 P1652 High-Reliability Control Circuit Board

Description

Key Technical Specifications

Product Introduction & Supply Chain Strategy

The Harland Simon H4890 P1652 is a specialized interface card primarily utilized in the control architecture of Quiet Room Desks and associated industrial signaling environments. Acting as a central termination point, this board manages complex signal routing through an array of fourteen terminal blocks and a high-density 26-pin interface. It is often paired with H4890 P1633 modules to provide a complete control and display solution for specialized operators’ consoles in utility and maritime applications.

From an inventory lifecycle perspective, the H4890 P1652 is a “Legacy Critical” component. Because these boards are often part of highly customized control room installations, finding functional replacements through standard OEM channels can be nearly impossible once the project reaches maturity. Procuring this module as New Surplus provides a strategic “Last-Time-Buy” advantage, securing an unused unit with zero operational fatigue. This significantly reduces the Total Cost of Ownership (TCO) by preventing the need for an expensive and time-consuming redesign of the entire desk control system when a single interface point fails.

Installation & Configuration Guide

Stage 1: Pre-Installation (Prep & Safety)

• Visual Audit: Cross-reference the “Issue” number (Iss 2) with your current failed board to ensure pin-out compatibility.
• Documentation: Label every wire connected to the 14 terminal blocks before removal.
• Safety: Disconnect all local power to the desk or control rack to prevent shorting during terminal reconnection.

Stage 2: Removal

• Cable Extraction: Carefully disconnect the 26-pin ribbon cable, pulling from the header and not the cable itself.
• Terminal Disconnection: Unscrew and remove the terminal blocks. If they are the plug-in type, pull them straight back.
• Unmounting: Remove the mounting screws from the PCB stand-offs.

Stage 3: Installation (Clone & Seat)

• Positioning: Secure the new H4890 P1652 onto the stand-offs.
• Interface Connection: Reattach the 26-pin ribbon cable, ensuring the polarity notch is correctly aligned.
• Wiring: Reconnect the terminal blocks exactly as labeled during the removal stage. Ensure no stray wire strands are touching adjacent terminals.

Stage 4: Power-On & Testing

• Voltage Check: Apply power and check for any local LED status indicators on the board (if applicable).
• Functional Test: Verify that all desk controls (switches, indicators, or adjustments) routed through this interface are responding correctly.
• Communication Audit: Ensure no “Comm Fail” errors appear on the associated H4890 P1633 display modules.

H4890 P1652

Firmware/Software Versions & Upgrade Notes

The H4890 P1652 is a hardware-intensive interface card; however, its functionality is governed by the revision level.

Revision Note: This board is an “Issue 2” (Iss 2). While often backward compatible with “Issue 1” slots, always verify that the jumper configurations (if present) match your original board’s settings. In some Harland Simon architectures, the P1652 acts as a passive or semi-passive router for the H5710P or R4745 sub-modules. If the system fails to recognize the new board, verify that the ribbon cable is not inverted and that the associated processor unit (e.g., 1747-L40A series) does not require a cold-start to re-poll the interface rack.

Frequently Asked Questions (FAQ)

• What is a “Quiet Room Desk” interface?

  It is a specialized signaling board used in control room furniture to connect operator inputs (buttons, sliders, headsets) to the main industrial PLC or processor unit.

• Is this compatible with Allen-Bradley hardware?

  Harland Simon systems frequently integrated with Allen-Bradley SLC 500 components (like the 1747 series). The P1652 often acts as the field-wiring bridge to these controllers.

• Why is New Surplus better than used for this board?

  The terminal blocks and ribbon headers on used boards often suffer from “mechanical creep” or oxidation after years of service. New Surplus ensures every connection point is pristine, providing superior signal integrity for sensitive low-voltage desk controls.

• Does it include the ribbon cable?

  Typically, the H4890 P1652 is sold as the board assembly only. If you require the 26-pin cable lead (R4745/R4764), please confirm inventory availability.

• What is the warranty?

  We provide a 1-year replacement warranty on this New Surplus unit, covering any manufacturing defects or component failures.