Products Description
Fives Group 502-03651-90 Memory Expansion Module

Technical Specifications
Model: 502-03651-90
Brand: Fives Group
Product Type: Rack mount memory expansion PCB assembly for legacy CNC control system
Module Feature:
Function: Memory expansion module for Fives Group CNC platform. Provides additional memory space for storing CNC part programs, tool offsets, system parameters and PLC ladder logic, communicates with main CPU through parallel backplane bus to expand system storage capacity for heavy horizontal boring mills and large machining centers.
Bus interface: Parallel backplane bus for high-speed bidirectional data exchange with CNC main CPU
Onboard components: Dynamic memory IC, memory control logic, address decoding circuit, data buffer chips, boot checksum logic
LED indicators: POWER, MEM, ACT, FAULT diagnostic lights
Hardware self-diagnosis: Memory read/write test, checksum verification, backplane bus integrity check
Programming software: Fives Group proprietary CNC software for memory capacity identification, program storage test and module diagnostic testing
Electrical Parameters
Backplane supply: +5VDC
Power consumption: Max 7.1W
Mechanical & Structure:
Mounting: Rack slot mount with gold finger edge connector
Weight: 0.91kg
Protection class: IP20
Environmental:
Operating temperature: 0℃ ~ +55℃
Ambient humidity: 5~85% non-condensing
Certification: CE
Status: Manufacturer discontinued legacy CNC memory expansion module
System compatibility
Compatibility description: 502-03651-90 belongs to Fives Group CNC control board family. Compatible with matched Fives Group main CPU and backplane bus interface boards. Widely deployed on heavy Fives Group horizontal boring mills.
Function
Function description: 502-03651-90 is dedicated memory expansion board manufactured by Fives Group. It extends system memory capacity for CNC controller, allowing storage of more large part programs, tool compensation data and machine parameters. The memory controller handles address mapping and data handshake with main CPU. It performs automatic checksum verification during power-up to ensure stored data integrity. It is legacy memory expansion spare for heavy CNC boring mills.
Installation
Installation steps: Follow lockout/tagout safety procedure before installation. Cut off rack +5V backplane power. Insert 502-03651-90 board into rack slot and secure gold finger connector. Power on rack, verify MEM and ACT LED indicators, run memory diagnostic test, confirm system recognizes expanded memory space and test program save/load operation.
Interface
Interface list: Backplane gold finger connector,on-board POWER / MEM / ACT / FAULT LED indicators for Fives Group 502-03651-90.
Diagnostic
Troubleshooting: System cannot detect memory board: Check backplane gold finger contact or hardware compatibility. FAULT LED lit: Memory chip failure, data checksum error or backplane communication fault. Program data corruption: Aging memory IC, power fluctuation or electrical interference.

Product Brief
Brief description: 502-03651-90 is Fives Group legacy memory expansion board,to expand CNC storage for part programs and system parameters on heavy CNC boring mills,discontinued CNC memory PCB spare.