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FANUC A17B-3900-0124
Product Name
FROM and SRAM memory module for Fanuc robot controllers.
Product Introduction
This plug in memory module provides nonvolatile flash storage and battery backed static memory for Fanuc robot controller system software, ladder logic, programs, variables, and calibration data. It installs on or interfaces with the main CPU board according to the controller architecture.
Detailed content
Technical Specifications
Part number: A17B 3900 0124.
Alternate reference: A20B 3900 0284 in supplier listings.
Module type: FROM and SRAM subboard.
FROM capacity: 32 MB flash memory.
SRAM capacity: 2 MB static RAM.
Compatible controllers: Fanuc R 30iB and R 30iB Mate series.
Mounting: horizontal board to board plug in on the main CPU assembly.
Cooling: natural convection within the controller cabinet.
Operating temperature: 0 to 45 °C.
Functional Features
Stores system firmware, option software, and boot images in FROM.
Retains robot programs, variables, offsets, and calibration data in SRAM with battery support.
Plug in design for direct replacement of degraded memory hardware.
Supports full controller backup and image restoration procedures.
Reduces downtime caused by corrupted or insufficient memory storage.
Application Scenarios
R 30iB robot controller memory upgrades and replacements.
R 30iB Mate controller program and system data storage.
Robot mastering data retention and disaster recovery.
Maintenance spare holdings for production robotic cells.
Performance Parameters
32 MB nonvolatile flash space for system and option software.
2 MB battery backed RAM for active variables and user programs.
Controller boot support through the main CPU memory interface.
Data retention governed by controller backup battery and proper shutdown procedure.
Material And Construction
Multilayer memory printed circuit board.
Flash memory integrated circuits.
Static RAM devices with backup battery circuit coordination.
Board to board connector with gold plated contacts.
Industrial grade components rated for control cabinet environments.
Working Principle
The main CPU reads system software and option data from FROM during boot. Active robot programs, variables, and temporary data are processed in SRAM. The controller backup battery maintains SRAM contents during power off. When the module is replaced, a previously saved image is loaded to restore firmware, programs, and calibration values.
Installation Requirements
Install only in R 30iB or R 30iB Mate main CPU configurations confirmed by the hardware manual.
Seat the board to board connector fully without angular force.
Maintain cabinet airflow and temperature within 0 to 45 °C.
Restore the saved FROM/SRAM image after physical replacement.
Usage Precautions
Perform a complete controller backup before removing the module.
Use antistatic handling and avoid touching connector pins or chips.
Verify controller backup battery voltage before commissioning.
Do not use this module in R 30iA or earlier controllers without confirmed compatibility.
Validate firmware version after restoration to prevent parameter mismatch.
