Fanuc Servo Motor A06B-0246-B101 A06B0246B101 AO6B-O246-B1O1

FANUC A06B-0246-B101 | AC22/2000i AC Servo Motor — Straight Smooth Shaft / i1000 Encoder / 22 Nm Class / 2000 rpm

AC22/2000i — Where This Motor Fits

The A06B-0246-B101 carries the AC22/2000i designation: 22 Nm stall torque class at 2,000 rpm maximum speed from FANUC's Alpha C servo motor series. The 22 Nm torque class positions it between the lighter α12/3000 (12 Nm) and the heavier α30/1200 (30 Nm) motor classes — appropriate for primary feed axis drives on medium-to-large CNC machining centres and turning centres where sustained torque at moderate speed is the design requirement.

At 2,000 rpm maximum speed, the priority is torque authority rather than high traverse rate. On a 10mm pitch ballscrew in direct coupling, 2,000 rpm produces 20 m/min — adequate for most machining centre feed axis rapid traverse requirements while delivering the 22 Nm continuous torque that sustains cutting forces on heavier machine structures.

The B101 configuration carries a straight smooth shaft — designated SLK, meaning no keyway. The coupling hub mounts via friction clamping on the plain shaft diameter. This shaft style requires correct hub clamping torque at installation and periodic inspection, as friction clamping can develop slip under sustained reversing loads if the clamping force degrades over time. Confirm the existing coupling hub's bore matches the smooth shaft specification before fitting.

Key Specifications

i1000 Encoder — Incremental, Homing Required

The i1000 is an incremental encoder. At each power-up, a reference-return cycle is required to establish the axis position reference before the machine can produce parts. This is standard and expected behaviour for machines built with Alpha C series incremental encoder motors. If absolute position on power-up without homing is required, the motor variant with an absolute encoder is the correct specification.

FAQ

Q1: What does the SLK (smooth shaft) mean for coupling selection?

SLK identifies a straight shaft with no machined keyway. Torque transmission relies entirely on friction clamping between the coupling hub bore and the shaft surface. The hub must be a smooth-bore friction type correctly sized for the shaft diameter. The hub locking torque must be applied at installation to the value specified by the coupling manufacturer. On a 22 Nm motor under reversing loads, an incorrectly torqued friction-clamp hub can develop micro-slip over service life — confirm hub installation torque and inspect periodically.

Q2: What amplifiers are compatible with the A06B-0246-B101?

The AC22/2000i class pairs with FANUC Alpha C series SVM amplifier modules from the A06B-6079 or A06B-6096 FSSB family at the appropriate current rating for the 22 Nm motor class. Confirm the specific amplifier model and its rated current against the motor's rated current before pairing. This motor is not compatible with Beta series amplifiers.

Q3: The machine requires homing at every power-up. Is this because of the i1000 encoder?

Yes. The i1000 is incremental — it has no absolute position memory and requires a reference-return cycle at each power-up to establish the axis datum. This is normal operating behaviour for machines equipped with Alpha C incremental encoder motors. For absolute position without homing, a motor variant with an absolute pulsecoder is needed.

Q4: After replacing the motor with A06B-0246-B101, the axis following error is larger than before. What should be checked?

Confirm the CNC's motor type parameter matches the AC22/2000i specification. Verify the encoder cable is fully seated at the amplifier feedback connector. Check the smooth-shaft coupling hub — a hub that is not fully clamped on the plain shaft creates mechanical misalignment that adds friction, which manifests as a following error before the coupling fails mechanically.

Q5: Where is the A06B-0246-B101 sourced?

Through the FANUC Alpha C motor aftermarket — specialist CNC motor dealers and repair companies offer exchange, tested surplus, and rebuild services. Confirm the B101 suffix (straight smooth shaft, i1000) from the installed motor's nameplate before ordering. Exchange programs typically require the failed motor as a core return.