Fanuc A16B-1212-0100-01 Power Unit for CNC Control Systems

Product Overview

The Fanuc A16B-1212-0100-01 is a power unit designed for use in Fanuc computer numerical control systems. This module converts incoming AC power to the regulated DC voltages required by the CNC main processor, servo amplifiers, spindle drives, and I/O modules. The power unit is a critical component within the Fanuc CNC cabinet, ensuring stable and noise-free power delivery to sensitive control electronics. The A16B-1212-0100-01 is typically found in Fanuc Series 0, 15, 16, 18, and 21 control systems, providing reliable performance in demanding machine tool environments including machining centers, lathes, and grinding machines. The unit is built with overcurrent, overvoltage, and overtemperature protection to safeguard the CNC system from electrical faults.

Key Features of Fanuc A16B-1212-0100-01

The power unit incorporates multiple isolated DC output rails to separately supply the logic circuits, servo interface, and spindle control sections of the CNC. The input stage includes an EMI filter to reduce conducted noise from the AC line, preventing interference with the CNC's sensitive signal processing. The switching power supply topology achieves high efficiency, reducing heat generation and improving reliability. The module includes LED indicators for input power presence, output voltage status, and fault conditions, enabling rapid diagnosis of power-related issues. The unit is designed for easy replacement within the CNC rack, with a standardized form factor that aligns with Fanuc backplane connectors.

The A16B-1212-0100-01 supports an input voltage range suitable for global industrial power systems, typically 200 to 240 V AC or 380 to 480 V AC depending on configuration. The output voltages provided by the unit include +24 V DC for I/O and relay circuits, +5 V DC for logic, and ±15 V DC for analog signal processing. The power unit includes internal fusing on both input and output lines, with accessible fuse holders for field replacement. Thermal monitoring circuits reduce output current or shut down the unit if internal temperatures exceed safe limits, protecting both the power unit and the connected CNC modules. The unit operates with forced air cooling provided by the CNC cabinet's cooling system.

Technical Specifications

• Manufacturer: Fanuc Corporation

• Part Number: A16B-1212-0100-01

• Product Type: CNC Power Unit / Power Supply

• Input Voltage: 200 to 240 V AC or 380 to 480 V AC (depending on variant)

• Input Frequency: 50/60 Hz

• Output Voltages: +24 V DC, +5 V DC, ±15 V DC typical

• Output Currents: Dependent on configuration

• Protection Features: Overcurrent, overvoltage, overtemperature

• EMI Filtering: Internal

• Indicators: Power OK, fault status LEDs

• Cooling: Convection with forced air assist from cabinet

• Mounting: Rack mount, Fanuc standard dimensions

• Operating Temperature: 0 to +45 °C typical

• Certifications: CE, UL (per Fanuc compliance)

Functional Description

The Fanuc A16B-1212-0100-01 power unit receives incoming AC power from the machine's main disconnect and converts it to the DC voltages required by the CNC control system. The input rectifier converts AC to a high-voltage DC bus, which is then switched at high frequency through a transformer to provide isolation and voltage transformation. The secondary outputs are rectified, filtered, and regulated to the precise voltages needed by the CNC modules. The power unit continuously monitors its output voltages and currents; if any output falls out of regulation or exceeds its current limit, the unit asserts a fault signal to the CNC processor, which may initiate an emergency stop or display an alarm message. The unit also includes a discharge circuit that safely bleeds stored energy from the internal capacitors when power is removed, preventing electrical shock hazard during maintenance. In multi-axis CNC systems, the power unit may also supply the DC link voltage for servo amplifiers, with regenerative capability to handle energy returned from decelerating axes.

Applications

The Fanuc A16B-1212-0100-01 power unit is used in all Fanuc-controlled machine tools and industrial robots that require a centralized power supply. Typical applications include vertical and horizontal machining centers, CNC lathes and turning centers, grinding machines, electrical discharge machines, and laser cutting systems. The unit is also found in Fanuc robotic controllers for material handling and welding applications. For maintenance and repair operations, this power unit provides a direct replacement for failed units in existing Fanuc systems, restoring CNC functionality with minimal downtime. CNC service centers and machine tool rebuilder's stock this power supply to support legacy Fanuc equipment operating in production environments worldwide.