New Fanuc A06B-0202-B200 AC Servo Motor — αiF 1/5000, Straight Keyed Shaft, A1000 Absolute, No Brake

Product Overview

Part Number: A06B-0202-B200

Also Searched As: A06B0202B200, FANUC A06B-0202-B200, Fanuc A06B0202B200

Motor Model: αiF 1/5000

Condition: New Classification: Fanuc Alpha iF Series AC Brushless Servo Motor — 1 Nm Stall Torque, 5,000 rpm Max Speed, Straight Shaft with Keyway, No Brake, Alpha i A1000 Absolute Pulse Coder, IP65

New — Not Refurbished, Not Exchange Stock

The A06B-0202-B200 on this listing is new. That distinction has real meaning when the component in question provides position feedback to a precision CNC axis and its coupling alignment determines how accurately that axis positions.

A new motor arrives with factory-calibrated A1000 encoder alignment, bearings at zero accumulated hours, seals that have never been exposed to coolant mist or machining debris, and a shaft ground to Fanuc's dimensional specification. Every one of those factors affects either how long the motor will run before needing attention or how accurately the axis it drives will perform from day one. For facilities that set a high bar for reliability and cannot afford the diagnostic uncertainty that comes with a refurbished unit of unknown history, new is the specification that makes sense.

Technical Specifications

Straight Shaft with Keyway: Why the Shaft Configuration Matters

The defining feature of the A06B-0202-B200 within the αiF 1/5000 family is its straight shaft with keyway — the ST, KEY configuration in Fanuc's motor designation system.

Three shaft configurations exist across the A06B-0202 series. The B000 carries a taper shaft with key: self-centering geometry that makes hub removal and reinstallation predictable across multiple service events, at the cost of requiring a draw bolt for proper hub engagement. The B100 carries a straight smooth shaft (SLK): friction-clamped coupling engagement, straightforward to install, no key to manage. The B200 — this motor — carries a straight shaft with a machined keyway: positive torque transmission through the key, without the taper geometry.

The straight-plus-key configuration is the correct choice when the driven coupling hub was designed around a keyed bore. Gear pulleys, synchronous belt drive hubs with parallel bores, custom-machined coupling flanges, and any coupling design where a key provides the primary torque path all require a keyed motor shaft. At 1 Nm stall torque, the mechanical stress on the key is well within the limits of standard key material and geometry — the keyway configuration here is about coupling interface compatibility, not about needing the key for any structural torque transmission reason.

The practical upside of the straight-plus-key over a taper shaft for some installations: hub removal on a straight keyed shaft is simpler. There is no press-fit taper to break free, no draw bolt to manage, and no risk of the hub seizing on the taper after years of thermal cycling. A puller on the hub face and the hub comes off cleanly. For machines where motor access is restricted and motor swaps need to be done quickly, that simplicity has real maintenance value.

When ordering a replacement A06B-0202-B200, the shaft configuration on the existing motor must be confirmed. A B000 (taper) hub will not fit a B200 (straight) shaft, and a B200 key hub cannot engage correctly on a B100 smooth shaft. Shaft type determines coupling hardware compatibility absolutely.

1 Nm, 5,000 rpm: The αiF 1/5000 in Its Operating Context

The αiF 1/5000 is the entry-level model of the Fanuc Alpha iF servo motor series, and like any correctly specified motor, its value lies in the match between its capabilities and the demands of the axes it serves.

One Newton-metre of stall torque is adequate for the sustained load demands of lightweight CNC auxiliary axes: compact tool magazine drives, ATC arm positioning mechanisms, secondary positioning axes on multi-axis machines, and C-axis or live tool drives on small turning centres where the rotating mass is low. The 1 Nm stall torque does not represent a limitation — it represents the correct sizing for axes where loading a heavier motor would add mass and inertia without contributing any useful additional torque at the operating conditions the axis actually experiences.

Five thousand rpm maximum speed is substantial for a motor this compact. On a 5mm pitch ball screw in direct coupling, 4,000 rated rpm translates to 20 m/min of linear traverse. For the compact axes this motor serves, that is rapid traverse performance that keeps cycle time competitive. The 5,000 rpm ceiling provides headroom above rated speed in the field-weakening region for applications where brief above-rated-speed operation suits the duty cycle.

0.5 kW at 95% power factor. The motor draws very little reactive current for its output class — a useful characteristic on machines with multiple servo axes sharing a common supply, where the cumulative reactive loading across all axes adds up to a real supply sizing constraint.

A1000 Absolute Encoder: The Operational Difference That Matters Every Shift

Every A06B-0202-B200 ships with the Alpha i A1000 serial absolute pulse coder — 1,000,000 pulses per revolution, multi-turn absolute position retained through power-off by the backup battery in the Fanuc αi servo amplifier.

The operational consequence is simple and repeatable: every time the CNC powers up, the axis coordinate is immediately known. There is no reference-return cycle. No supervised homing traverse. No waiting for the axis to reach its reference marker before the machine can enter automatic mode. When the operator turns the machine on in the morning, or when the CNC recovers from a power interruption mid-shift, every absolute-encoder axis resumes from exactly the position it held at power-down.

For machines that run multiple shifts with power cycling between them, this translates to a few minutes saved on every startup — multiplied across every working day. For machines that stop mid-program on an alarm or power interruption, this means the recovery is immediate rather than requiring a supervised homing procedure before production can resume.

At 1,000,000 counts per revolution, the position loop closes at nanometre-scale resolution on typical ball screw pitches. The CNC interpolation quality and axis following error performance that precision machining depends on are built on the quality of this feedback signal — and on a new motor with factory-calibrated encoder alignment, that signal starts from exactly where Fanuc's design intends it to.

Battery note: The A1000 multi-turn counter is backed up by a battery in the servo amplifier, not in the motor. Replace this battery promptly when the Fanuc CNC issues a low battery alarm — running the battery to depletion resets the counter and forces a one-time re-referencing procedure.

No Brake: The Right Specification for Horizontal Axes

The B200 suffix carries no electromagnetic brake. This is the standard and correct configuration for horizontal axes and any axis where no net gravitational force acts along the direction of shaft rotation.

Position at rest on these axes is maintained by the αi servo amplifier's servo lock — the position loop active, the A1000 feeding back 1,000,000 counts per revolution, and the amplifier continuously correcting to the commanded shaft angle. On horizontal axes, this hold is entirely reliable. The shaft does not drift between commanded positions when the servo is active.

The no-brake configuration brings practical advantages: no 24V DC brake circuit to wire and protect in the panel, no brake relay or timing logic in the CNC startup sequence, no brake disc wear accumulating over the motor's service life, and a lighter and shorter motor body than the equivalent braked variants.

Where the axis is vertical — or carries any gravitational load component along the shaft rotation direction — servo lock at servo-off is not adequate, and the axis requires a braked motor. The braked equivalents within the A06B-0202 family are the B300 (taper shaft, 24V spring brake, A1000 absolute) and the B400 (straight smooth shaft, 24V spring brake, A1000 absolute). A straight-keyed-shaft braked variant would require confirmation of the specific part number. The A06B-0202-B200 is correctly specified for confirmed horizontal axes only.

A06B-0202 Family: Configuration Reference

The B200 occupies a specific configuration position: straight shaft engagement geometry, positive key torque transmission, absolute encoder feedback, no brake. The correct replacement for any axis fitted with a B200 is another B200 — the shaft geometry determines the coupling hardware, and the coupling hardware is already installed on the machine.

Compatible Amplifiers and CNC Systems

The A06B-0202-B200 operates with Fanuc αi series servo amplifiers (αiSV) — specifically the αiSV 4 for this motor's 0.5 kW / 1 Nm power level. Compatible CNC platforms include Fanuc Series 0i-D, 0i-F, 15i, 16i, 18i, 21i, 30i-A, 30i-B, 31i-A, 31i-B, and 32i. Not compatible with original α series (non-i) amplifiers or Fanuc β series drives.

On new motor installations, confirm the CNC axis parameters are set to the αiF 1/5000 motor type from Fanuc's servo parameter database before running production. Some recent CNC versions will auto-detect the motor type from the A1000 pulse coder data at startup — verify the auto-detected result matches the expected configuration before proceeding.

Typical Applications

Tool magazine and ATC mechanism drives. Random-access tool magazine indexing, ATC arm positioning, and carousel drives on Fanuc-controlled machining centres where the light mechanism load and the 5,000 rpm ceiling allow fast magazine cycle times with absolute position confirmation on every power-up.

Compact machining centre feed axes. X, Y, and Z drives on small drill-tap centres and compact 3-axis machining centres where the axis load demands and required traverse speed fall within the αiF 1/5000 torque-speed envelope, and the keyed shaft matches the existing coupling hardware in the machine.

C-axis and live tool positioning on CNC turning centres. C-axis drives and live tool orientation axes where precise angular positioning with absolute encoder feedback suits the axis kinematic requirement, and the straight keyed shaft interfaces correctly with the drive mechanism's coupling design.

Rotary indexing and positioning axes. Rotary table drives, B-axis tilting mechanisms, and angular positioning axes on multi-axis machining centres where the load inertia and positioning speed requirements match the αiF 1/5000 specification.

FAQ

Q1: What is the difference between the B200 and the B000 or B100 within the same αiF 1/5000 family?

All three share identical torque (1 Nm), speed (5,000 rpm), power (0.5 kW), and encoder (A1000 absolute) specifications. The difference is purely the shaft configuration. The B000 has a taper shaft with keyway — self-centering taper geometry that ensures precise hub alignment on installation and removal. The B100 has a straight smooth shaft — friction-clamp coupling engagement, no key. The B200 has a straight shaft with a machined keyway — positive torque transmission through the key, straight bore coupling engagement. Order the variant whose shaft matches the coupling hub already installed on the machine.

Q2: Does this motor require a homing cycle on every CNC power-up?

No. The A1000 is a serial absolute encoder — it retains multi-turn shaft position through power-off by the backup battery in the Fanuc αi servo amplifier. The axis coordinate is re-established immediately when the CNC powers up, with no homing movement required. This distinguishes the B200 from the incremental encoder variants (B201 if it exists) where reference-return is mandatory on every power-up. After installing a new motor for the first time, a one-time position synchronisation is required to match the absolute counter to the machine coordinate — this is a standard commissioning step, not a recurring operational requirement.

Q3: Which Fanuc amplifier is required for the A06B-0202-B200?

The motor requires a Fanuc αi series servo amplifier (αiSV 4) for this 0.5 kW power class. Compatible CNC platforms include Fanuc Series 0i-D, 0i-F, 16i, 18i, 21i, 30i, and 31i. Original α series (non-i) amplifiers and Fanuc β series drives are not compatible — the A1000 encoder uses a serial protocol that only αi generation amplifiers support. Always verify axis parameters are configured for the αiF 1/5000 motor type after installation.

Q4: Why choose a new A06B-0202-B200 over a refurbished unit?

A new motor provides factory encoder calibration (alignment affects axis positioning accuracy), bearings at zero accumulated hours (condition directly determines time to next failure), intact factory sealing (protects against coolant ingress on the axis), and shaft geometry ground to Fanuc specification (critical for coupling engagement quality on a keyed shaft). Refurbished motors vary in quality depending on the rebuild facility — bearing replacement standards, encoder realignment process, and shaft inspection procedures differ. For a precision CNC axis where these variables have direct consequences on performance and reliability, new eliminates those unknowns entirely.

Q5: Can a B200 safely replace a B300 (braked variant) on a machine?

Only if the axis is confirmed horizontal with no gravitational load component along the shaft rotation direction. The B300 carries a spring-applied electromagnetic brake providing mechanical holding at servo-off — a safety function required on vertical axes and inclined feeds where gravity would cause movement when the servo is de-energised. The B200 has no brake. Fitting a B200 where a B300 was specified on a vertical axis removes that mechanical safety hold. If the original motor was a B200, replacement with another B200 is straightforward. If the original was a B300, the axis design must be re-evaluated before fitting a brakeless motor — this is an engineering decision, not a simple swap.