A06B-0147-B088 Fanuc AC Servo Motor A06B0147B088 AO6B-OI47-BO88

Fanuc A06B-0147-B088 | ALPHA Series AC Servo Motor A22/2000 — 3.8kW, Straight Shaft, A1000 Encoder

Part Number: A06B-0147-B088

Series: ALPHA AC Servo Motor

Model: A22 / 2000

Status: Discontinued by Manufacturer — Refurbished & Surplus Stock Available

Condition: Refurbished / Surplus

Overview

The Fanuc A06B-0147-B088 is a 3.8 kW AC servo motor from Fanuc's ALPHA series — model A22/2000 — carrying a straight shaft and the A1000 encoder as its feedback device. Rated at 2,000 RPM with 15A continuous current draw at 157V three-phase, 133Hz, this is a substantial mid-frame motor built for the heavy feed axis demands of small to medium CNC machine tools where sustained torque under real cutting load is the measure of the motor's value.

The A1000 encoder is what distinguishes this variant from the I64 and A64 equipped versions within the same A22/2000 family. At 1,000,000 pulse counts per revolution, the A1000 represents a step change in feedback resolution compared to the 64,000 ppr I64 — sixteen times the position granularity, resolving shaft position at a level of detail that directly benefits axis accuracy in precision contouring, fine finishing passes, and high-accuracy positioning on machines where surface quality and dimensional tolerance are the defining performance criteria.

Fanuc has discontinued this motor, but the machine tools it was fitted to continue running in production environments worldwide.

For the facilities maintaining them, the A06B-0147-B088 remains actively traded through the refurbished and surplus market.

Key Specifications

The A22/2000 Motor — Heavy Torque at Moderate Speed

The AC22 torque class — 22 Nm stall torque — places this motor decisively above the AC12 and AC6 units used on lighter axis drives. At 3.8 kW continuous output from a 2,000 RPM ceiling, the A22/2000 was designed for axes where the mechanical load is real and constant: X, Y, and Z drives on mid-range vertical machining centres, Z-axis drives on turning centres with heavy turret arrangements, and axes where the servo system must resist cutting forces without the velocity loop hunting or current-limiting that occurs when a motor is operating near its continuous rating ceiling.

The 15A continuous current draw at 157V reflects the electrical load this motor places on the servo amplifier. At 133Hz rated frequency, the ALPHA servo amplifier generates the drive conditions the motor requires from a standard 200–240VAC mains supply — the 133Hz figure is the internal operating frequency at rated speed, produced by the amplifier's inverter stage.

For maintenance engineers, the relevant parameter is the 15A current class, which governs amplifier module selection, cable sizing, and the thermal management specification for the drive cabinet.

The 2,000 RPM maximum speed suits direct-coupled ballscrew axis configurations where the motor speed maps to practical rapid traverse rates without requiring intermediate gearing. At 22 Nm stall torque, the motor provides the axis stiffness that maintains feedrate accuracy under aggressive cutting conditions — a parameter that matters more on production machines under sustained load than peak speed does.

A1000 Encoder — High-Resolution Feedback

The A1000 is what makes the B088 variant distinctive within the A22/2000 family. Where the more common I64 provides 64,000 pulses per revolution and the A64 provides an absolute version at the same resolution, the A1000 encoder delivers 1,000,000 counts per revolution of shaft position data to the ALPHA servo amplifier.

That sixteen-fold resolution increase over the I64 has practical consequences at the axis level.

The servo drive's velocity loop has finer position data to work with at every moment in the motor's rotation — which produces smoother velocity profiles, lower velocity ripple at slow feedrates, and more precise position endpoints.

On machines doing precision contouring where surface finish is a direct function of velocity smoothness, or holding tight dimensional tolerances where position accuracy at low feedrate matters, the A1000's resolution advantage translates into measurable improvement in output quality.

The A1000 is an absolute encoder — it retains shaft position through power interruptions without a homing cycle.

On machine startup, the servo drive reads the current absolute position directly, and the CNC has full axis position knowledge before any motion is commanded.

This eliminates the homing sequence that I64-equipped axes require at every power-on.

When sourcing a replacement A06B-0147-B088, the A1000 encoder specification must be matched exactly. Substituting a motor with an I64 or A64 encoder requires servo drive parameter changes, loss of the absolute position function (in the case of the I64), and may affect the accuracy characteristics of the axis if the drive's velocity loop parameters were tuned for the A1000's higher resolution.

Straight Shaft and Drive Train Integration

The plain straight shaft on the A06B-0147-B088 uses servo coupling clamping force for torque transmission to the driven component. For the 22 Nm stall torque this motor generates, coupling selection and installation torque matter: the coupling must be rated for the motor's torque output and the shaft clamping force must be set to specification to prevent progressive coupling slip under sustained axis loading.

On a motor of this power class, coupling slip produces position error that accumulates without triggering an immediate alarm — it shows up as axis positioning scatter over time.

The #7000 and #7008 sub-variants within the B088 specification carry the same electrical and encoder characteristics but differ in shaft keyway machining.

The base B088 (plain) and #7000 suffix carry no keyway; the #7008 has a keyway for keyed coupling hub arrangements. Confirming which shaft sub-variant is installed on the machine before ordering a replacement is the straightforward step that prevents a coupling mismatch on arrival.

Drive & Control Compatibility

The A06B-0147-B088 is compatible with Fanuc ALPHA series SVM servo amplifier modules rated for the 15A continuous current class and integrates with Fanuc CNC controls including Series 0, 0i, 15, 16, 18, and 21.

The servo amplifier must be parameterised with the motor type code for the A22/2000 with A1000 encoder — this is the parameter that governs the velocity loop response, current limits, and position feedback scaling.

Given this motor's age and the range of drive and control upgrades that machines may have received since original build, confirming that the installed amplifier supports the A1000 encoder interface before installing a replacement is a necessary commissioning step.

FAQ

Q1: What makes the A1000 encoder different from the I64 fitted to other A22/2000 variants?

The A1000 provides 1,000,000 pulses per revolution — sixteen times the resolution of the I64's 64,000 ppr. It is also an absolute encoder, retaining shaft position through power cycles without a homing sequence. The I64 is incremental and requires homing at each machine startup.

The A1000's higher resolution improves velocity loop smoothness and position accuracy at low feedrates, which directly benefits surface finish quality and dimensional accuracy on precision machining operations. When replacing the B088, the A1000 encoder specification must be matched — fitting an I64 or A64 motor requires parameter changes and loses the absolute function.

Q2: What servo amplifier is required for the A06B-0147-B088?

The motor requires a Fanuc ALPHA series SVM amplifier module rated for at least 15A continuous output current.

It integrates with Fanuc CNC controls including Series 0, 0i, 15, 16, 18, and 21.

The motor type parameter in the amplifier must be set to match the A22/2000 with A1000 encoder specification. An incorrect motor type code affects velocity loop tuning and current limits — always verify this parameter after any motor replacement before running the axis under load.

Q3: Does this motor need a brake for vertical axis applications?

The A06B-0147-B088 has no integrated brake. For vertical axes carrying significant load weight — a spindle head, a heavy turret, or a substantial axis carriage — the absence of a mechanical brake means position holding when the servo is inactive relies entirely on the drive's active torque retention.

For gravity-loaded vertical axes where axis drop on E-stop or power loss is a risk, the braked variant within the A22/2000 family (B177 suffix) is the correct specification. The B088 is appropriate for horizontal axes and lightly loaded vertical drives where active servo holding is adequate.

Q4: Are the #7000 and #7008 shaft sub-variants electrically equivalent?

Yes. The #7000 carries a plain straight shaft with no keyway; the #7008 carries a keyway machined into the straight shaft for use with keyed coupling hubs. Both sub-variants are electrically identical — same 3.8kW output, same 22Nm torque, same 157V / 133Hz / 15A specification, and same A1000 encoder.

The shaft machining is the only difference. Confirm which sub-variant is installed on the machine before ordering to ensure the coupling interface matches.

Q5: What are the key inspection points for a used A06B-0147-B088?

Measure three-phase winding resistance for phase balance and check insulation resistance to earth — both confirm winding integrity.

Rotate the shaft by hand to assess bearing condition; at 3.8kW and 22Nm stall torque, the front bearing carries significant radial load and is one of the more common wear points on motors with extended service histories. Inspect the A1000 encoder connector for corroded or damaged pins and the cable exit for strain relief damage. 

Check the shaft end for fretting or coupling contact marks. A bench run-up to rated speed with absolute encoder position verification is the correct final check before the motor is committed to a production axis.