FANUC A06B-0061-B103 βiS 2/4000 AC Servo Motor with Straight Smooth Shaft

It is intended for precise machine-axis control with a compatible FANUC servo amplifier and CNC system. Correct replacement depends on matching the shaft, feedback device, mounting arrangement, connectors and motor parameters—not only the βiS 2/4000 model name.

Confirmed A06B-0061-B103 Specifications

• Manufacturer: FANUC
• Part number: A06B-0061-B103
• Product type: Three-phase AC servo motor
• Motor model: βiS 2/4000
• Rated output: 0.5 kW
• Stall torque: 2 N·m
• Stall current: 3.3 A RMS
• Rated speed: 4,000 min⁻¹
• Maximum speed: 4,000 min⁻¹
• Maximum torque: 7 N·m
• Output shaft: Straight smooth shaft without keyway
• Holding brake: Not fitted
• Feedback device: βiA128 absolute pulse coder

Why the B103 Configuration Matters

The B103 specification identifies the straight, non-keyed shaft arrangement combined with βiA128 feedback. A coupling designed for a tapered or keyed shaft cannot be assumed to fit this version, even when the motor body and performance class look similar.

βiA128 Absolute Position Feedback

The βiA128 pulse coder returns rotor position and speed information to the servo-control system. FANUC documentation associates this encoder choice with applicable FS0i configurations. Confirm that the original control and servo amplifier support the same feedback type.

Absolute-position retention relies on the corresponding backup-battery circuit. Battery condition and the approved encoder-disconnection procedure should be checked before motor removal.

B003, B103 and B403 Comparison

A06B-0061-B003 uses a tapered shaft without a brake, while A06B-0061-B103 uses a straight smooth shaft without a brake. A06B-0061-B403 is a separate straight-shaft version fitted with a holding brake. These configurations should not be interchanged without checking the original machine design.

IP67 and Modification-Suffix Check

The sealed A06B-0061-B103#0100 is specifically identified as an IP67 version. This protection rating must not be assigned automatically to an unsuffixed A06B-0061-B103. Always compare every character following the base part number.

Replacement Verification

Before ordering, verify the full nameplate number, straight non-keyed shaft, no-brake requirement, βiA128 feedback, connectors, flange dimensions, compatible FANUC amplifier and existing CNC motor parameters.

Tested FANUC Motor Supply

REACO CNC supplies the FANUC A06B-0061-B103 servo motor for maintenance, replacement and machine-down requirements. Each available unit is 100% tested before shipment. A clear original nameplate photo can help us verify the exact configuration.

Worldwide DHL/UPS/FedEx shipping. Contact REACO CNC for stock, condition, price and delivery time.