A20B-8101-0180 Fanuc Power Supply Board A20B81010180 A2OB-8IOI-OI8O

A20B-8101-0180 | FANUC A20B-8101 Series Power Supply PCB — 018x Range / CNC and Servo Power Board

A20B-8101 — FANUC's i-Series and Servo Amplifier Board Family

The A20B-8101 series is a confirmed FANUC PCB family spanning main CPU motherboards, power supply boards, and servo amplifier boards across i-series CNC and robot controller platforms. Boards confirmed across the A20B-8101 series:

The A20B-8101-0180 at the 018x position is confirmed as a power supply PCB — occupying the board series' lowest confirmed range, consistent with a fundamental power supply role in the CNC or servo system architecture.

Key Product Information

Power Supply PCBs in the A20B-8101 Context

The A20B-8101 series confirms two power supply PCB positions — 018x (A20B-8101-0180) and 043x (A20B-8101-0430). Both serve defined power distribution roles within FANUC CNC or servo amplifier systems. Power supply PCBs in this context:

DC voltage regulation: Generating and stabilising the regulated supply voltages (typically 5V, ±15V, 24V) that power the control electronics, encoder interfaces, and communication hardware across the CNC or drive system.

Protection monitoring: Continuously monitoring supply rail voltages for overvoltage, undervoltage, and overcurrent conditions — generating protective shutdown signals when thresholds are exceeded to prevent damage to connected boards.

Inrush management: Controlling the charging of filter capacitors on power-up to prevent inrush current from tripping upstream protection devices — standard practice in precision industrial power supply design.

Application Scenarios

Power supply fault — i-series CNC or servo system: A FANUC CNC or servo amplifier system develops power supply level faults — incorrect supply voltages, power alarms, or multi-board instability tracing to a common supply rail. The A20B-8101-0180 is identified as the power supply PCB fault. Replacement restores correct power distribution.

Planned power board maintenance: A production facility maintaining FANUC i-series CNC or servo equipment stocks A20B-8101-0180 as a spare for the specific system in which it is installed.

FAQ

Q1: How do I confirm A20B-8101-0180 is the correct power supply board for my FANUC system?

Read the part number from the installed board's label. If it reads A20B-8101-0180, this is the confirmed replacement. Cross-reference with the applicable FANUC CNC or servo system maintenance manual's board layout diagram to confirm the power supply board's mounting position and output voltage specifications.

Q2: What symptoms indicate an A20B-8101-0180 power supply PCB failure?

Power supply PCB faults cause system-wide symptoms: multiple boards failing simultaneously, incorrect supply voltages measurable at the board's output terminals, power supply alarm codes on the CNC or drive display, or complete system failure to power up. Isolate by measuring the regulated DC supply rails at the PCB's output connectors before condemning the board — confirm the fault is in the supply itself, not in an overloaded downstream circuit.

Q3: Is A20B-8101-0180 the same as A20B-8101-0430 (the other confirmed A20B-8101 power supply PCB)?

Both are power supply PCBs in the A20B-8101 series, but at different positions (018x vs 043x). They serve different system configurations or have different output specifications. Always confirm from the installed board's part number label — never substitute one power supply board for another based on series family alone, as output voltage rails and connector pinouts differ between variants.

Q4: What safety precautions apply when replacing A20B-8101-0180?

Power the CNC or servo system completely down and lock out the mains supply before accessing the power supply board. Power supply PCBs carry higher-voltage circuits alongside logic-level signals — verify all supply rails are de-energised before handling. Handle with a grounded anti-static wrist strap on an ESD-safe surface. After fitting the replacement, verify all output voltages are within specification before enabling the connected boards.