|
| Place of Origin | JAPAN |
| Brand Name | FANUC |
| Certification | CE ROHS |
| Model Number | A20B-3900-0010 |
The FANUC A20B-3900-0010 is a 16MB FROM memory module used in 16i / 18i / 21i Model A controls.
Hardware lists for the Model A family place A20B-3900-0010 alongside A20B-3900-0070, and seller listings describe the part as a memory module or memory card rather than a general circuit board.
This is the kind of module that belongs in the controller’s program-memory structure rather than in the amplifier, display, or front-panel section.
For a product page, the clearest description is a 16MB FROM module for older FANUC i-Series controls.
That is a better fit for buyer intent and search indexing than vague language about “enhancing performance.”
| Parameter | Value |
|---|---|
| Part Number | A20B-3900-0010 |
| Brand | FANUC |
| Product Type | FROM Memory Module / Memory Card |
| Memory Capacity | 16MB |
| Commonly Listed Controls | 16i / 18i / 21i Model A |
| Product Family | A20B-3900 series |
| Typical Use | Program memory replacement |
A20B-3900-0010 should be treated as a program-memory board, not just as a generic PCB.
A maintenance guide and supporting documentation around this family show that these modules form part of the internal memory arrangement used by older i-Series controls.
In field repair, that makes exact identification important because memory boards with similar form factors can still serve different roles in the system.
Q1: What is the A20B-3900-0010 used for?
It is used as a 16MB FROM memory module in older 16i / 18i / 21i Model A controls.
In practical terms, that means it belongs to the program-memory side of the controller rather than to the servo, spindle, or operator interface section.
Q2: Why is exact matching important for this module?
Because memory boards in the A20B-3900 family can differ in both capacity and function.
The 16MB FROM identity is part of what defines A20B-3900-0010, so the safest service approach is to match the exact module number instead of relying only on family similarity.
Q3: Is this mainly a repair-market part?
Yes. The current market around A20B-3900-0010 is centered on replacement and service supply.
That makes it most relevant to maintenance departments, repair shops, and users supporting older i-Series controls that remain productive in the field.
Q4: Does this board have an SRAM function too?
The part itself is consistently identified as a 16MB FROM module.
Related technical documents for this family explain that FROM modules and SRAM functions are handled as distinct roles in the memory architecture.
In practice, that means A20B-3900-0010 should be selected as a FROM/program-memory part, not as a mixed FROM/SRAM substitute.
Q5: What should be checked before replacing A20B-3900-0010?
A technician should confirm the exact installed part number, verify the control generation, and make sure the observed problem actually belongs to the program-memory path.
It is also good practice to inspect the receiving connector and review any backup or restore procedure before removal.
Those final steps are practical engineering guidance supported by the module’s role in the internal memory structure of older i-Series controls.
Contact Us at Any Time
