FANUC A20B-8101-0050 PROFIBUS-DP Communication PCB

Overview

The A20B-8101-0050 is a PROFIBUS-DP communication PCB in the A20B-8101 family. Listings describe it as a PROFIBUS DP PCB, communication interface module, Profibus communication board, and Profibus master board.

Across those listings, the most consistent role is clear: this board is used for PROFIBUS-based fieldbus communication inside compatible FANUC control hardware.

Some listings tie it to robot-controller applications such as R-30iA / R-30iB, while others tie it to 31i CNC control applications.

The common point is the same PROFIBUS communication role, so the safest replacement approach is to confirm the exact installed controller platform and keep the same board model in the same communication-board position.

Technical Data

Applications

This board is suitable for installed FANUC control and robot systems that already use a PROFIBUS-DP communication interface in the A20B-8101-0050 board position.

It is especially relevant in communication-board replacement, controller repair, and fieldbus-interface maintenance where the original PROFIBUS structure must remain unchanged.

Replacement Guidance

Before ordering, confirm the installed board code, verify that the controller uses PROFIBUS-DP, and check whether the installed platform is a robot controller or a 31i-class CNC controller.

Since listings link this board to more than one FANUC platform, exact installed controller confirmation is especially important here.

FAQ

Q1: What kind of board is A20B-8101-0050?
It is a PROFIBUS-DP communication PCB. Listings describe it as a communication interface module, Profibus communication board, and Profibus master board, which places it in the communication layer of compatible FANUC hardware rather than in the motherboard, display, or servo section.

Q2: Why is the PROFIBUS-DP description important?
Because the fieldbus protocol is part of the board’s defining function. A controller already configured for PROFIBUS should keep the same communication-board type to preserve the installed network role and interface structure.

Q3: Is this board used in robots or CNC controls?
Listings connect it with both environments. Some identify it for R-30iA / R-30iB / R-30iB Plus robot controllers, while others link it to 31i CNC control applications.

That is why the installed platform should be checked directly before purchase.

Q4: What extra board details appear in listings?
Some listings describe it as a Profibus master board with a CPU chip and two integrated LEDs for board and communication status.

Those details are useful when visually confirming the installed board during service work.

Q5: What should be checked before buying?
Check the installed board code, confirm the controller uses PROFIBUS-DP, and verify whether the installed platform is the same robot-controller or CNC-controller environment already using A20B-8101-0050.

These are the main compatibility points for correct replacement.