FANUC A20B-8200-0580 31i-A5 Main PCB

Overview

The A20B-8200-0580 is a FANUC main PCB in the A20B-8200 series. Public industrial listings consistently identify it as a 31i-A5 MAIN PCB, and a FANUC maintenance-manual excerpt also maps this exact model to the 30i-A / 31i-A5 main board group.

That places it clearly in the main-board level of the CNC control hardware rather than in the accessory, I/O, or memory-only category.

As a main PCB, this board belongs to the central hardware structure of the installed control.

In practical replacement work, that means exact model continuity matters because the main board defines the original control platform, board-family position, and core hardware layout of the CNC unit. 

Public listings also show this model being handled as a board-level spare rather than a generic circuit board.

Technical Data

Application Value

This board is suited to installed FANUC CNC control systems that already use the 31i-A5 main-board structure.

It is especially relevant in controller repair, refurbishment, and main-board replacement where the original control platform must remain unchanged at the core-board level.

Because the part is publicly identified as a 31i-A5 MAIN PCB, it should be treated as a central control-board spare, not as a simple plug-in accessory.

Keeping the same model helps preserve the existing board-family structure and the original CNC hardware arrangement.

Selection Notes

The key checks are the exact part number, the A20B-8200 family, and the published identification of the board as a 31i-A5 MAIN PCB.

The public manual excerpt linking it to the 30i-A / 31i-A5 main board group is also useful for confirming the installed hardware family.

FAQ

Q1: What kind of board is A20B-8200-0580?
It is a FANUC main PCB. Public industrial listings consistently describe it as a 31i-A5 MAIN PCB, which makes it a core control-board component rather than a simple I/O or accessory board.

Q2: Why is the “31i-A5 MAIN PCB” description important?
Because that description defines the board’s role in the CNC hardware.

A board identified publicly in that way belongs to the control core of the installed unit, so it should be matched by exact model when replacing it. 

That is the most important compatibility point supported by the available listings.

Q3: Is there any public indication that this board belongs to the 30i/31i board family?
Yes. A public FANUC maintenance-manual excerpt maps A20B-8200-0580 to the 30i-A / 31i-A5 main board group.

That supports the public listing description and helps place the board in the expected CNC hardware family.

Q4: Why does exact part-number matching matter so much here?
Because this is a main PCB. Main boards define the central hardware structure of the installed control, so replacing them by approximate similarity is risky.

Public sources identify this board by exact model and by its main-board role, which makes exact matching the correct replacement approach.

Q5: What should be checked before ordering?
Check the installed part number, confirm the machine uses A20B-8200-0580, and verify that the original board is the same 31i-A5 main PCB type in the installed control hardware.

Those are the main compatibility points supported by the public references for this model.