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$225.00 USD
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The FANUC A20B-3900-0072 is an 8MB FROM memory module used to store CNC and servo system software in compatible FANUC i-Series controls. It is a plug-in DIMM-style module for the applicable CNC motherboard, not a complete control board or general-purpose memory card.
FANUC documentation lists A20B-3900-0072 as an 8M FROM module in the Series 16i/18i/21i/20i-A hardware family. The module is also described in the aftermarket as Program Memory C for selected 16i, 18i and 21i configurations.
A20B-3900-0072 Product Information
| Brand | FANUC |
| Model / MPN | A20B-3900-0072 |
| Product Type | FROM memory module / plug-in memory PCB |
| Memory Capacity | 8MB / 8M |
| Memory Type | FROM non-volatile system memory |
| Documented Function | CNC and servo system software storage |
| Common Designation | Program Memory C |
| Applicable Family | Selected FANUC 16i, 18i, 21i and related i-Series configurations |
| Related 8M Module | A20B-3900-0012; verify motherboard and software compatibility |
| Condition | New, refurbished, or used 90% new; subject to stock |
| Testing | 100% tested before shipment; test video available |
| Handling | Normally 1–3 business days |
| Shipping / ETA | DHL, UPS, or FedEx worldwide; typically 2–6 business days |
| Warranty | 1 year for new/refurbished; 3 months for used 90% new |
| Service / Packing | Free technical support; anti-static reinforced protective packing |
FROM Module Function
A FROM module contains the system software required by the CNC control. It is different from an SRAM module, which is associated with machine data such as parameters, programs and offsets. Replacing the FROM module does not automatically transfer the original machine configuration or software options.
Software and System Compatibility
Confirm the complete A20B-3900-0072 marking, PCB revision, CNC series, motherboard model, control generation, machining or turning software, system edition and option configuration. A blank module or one programmed for another machine may require the correct system software to be loaded before the control can operate.
Testing and Replacement Notes
REACO CNC checks the module label, PCB condition, memory devices, solder joints, edge connector and system recognition as applicable. Back up CNC parameters, PMC data, programs, offsets and other machine data before opening the control. Installation and software restoration should be performed by qualified FANUC personnel using the correct backup and boot procedure.
Related resources: FANUC CNC and robot parts and FANUC CNC board repair services.
Fast Global Delivery
- DHL, UPS, FedEx Global shipping.
- Expedited shipping available
- Packed in secure reinforced cartons for maximum protection during transport.
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