Fanuc AC Servo Motor A06B-1405-B103 A06B1405B103 AO6B-14O5-B1O3

FANUC A06B-1405-B103 | Alpha i Ai3/10000 AC Spindle Motor — 3.7/5.5 kW / 1500–10000 rpm / MZi / Flange Mount / Rear Exhaust

Ai3/10000 — Power and Speed Envelope

The A06B-1405-B103 is the Ai 3/10000 — 3.7 kW continuous and 5.5 kW in short-duty cycles across 1,500 to 10,000 rpm. It sits between the Ai 2/10000 (A06B-1404 series, 2.2/3.7 kW) and the larger Ai 8/8000 (A06B-1407 series) in the Alpha i spindle family, sharing the same mounting footprint and amplifier interface as the smaller Ai 2/10000 while delivering the higher continuous power the larger motor class requires.

The 1,500 rpm lower bound defines the constant-power zone's base. Below 1,500 rpm the motor operates in constant-torque mode — for low-speed drilling, tapping, and turning where maximum torque at reduced speed governs. From 1,500 rpm through 10,000 rpm, rated power is maintained across the full range by the spindle amplifier's field-weakening control.

The spindle amplifier current class must be sized for the Ai 3/10000's 5.5 kW peak — confirm the amplifier's current capacity before substituting the B103 for a lower-power variant on the same machine.

Key Specifications

Slick Shaft at 10,000 rpm — Why No Keyway

At 10,000 rpm, rotational balance of the shaft assembly is a meaningful parameter. A keyway slot introduces a geometric discontinuity in the shaft that requires correction in the balancing process. The plain slick shaft presents a clean, symmetric rotating surface — coupling hubs and pulleys fitted to the slick shaft can be precision-balanced as a matched assembly without compensating for the keyway's imbalance contribution.

At 5.5 kW peak, the torque loading on the coupling is modest compared to the larger spindle motor classes in the Alpha i range. A correctly installed friction-clamp coupling hub handles the Ai 3/10000's torque without slip under normal conditions. For belt-drive arrangements, the coupling hub specification must account for belt tension in addition to transmitted torque.

MZi Sensor — What It Enables

The MZi magnetic sensor at the motor rear generates continuous speed and rotor position feedback. It enables four spindle functions beyond simple speed regulation:

• Oriented stop — parks the spindle at a defined angular position for tool changes and workpiece loading
• Cs-axis control — converts the spindle into a programmable positioning axis for driven tool operations on mill-turn platforms
• Rigid tapping — synchronises spindle rotation and Z-axis feed at a fixed ratio throughout the threading cycle
• Spindle orientation — used in automated workpiece handling and probing cycles requiring repeatable spindle position

A failed or intermittent MZi signal causes CNC alarms on these functions while basic spindle rotation at speed may continue. Check sensor air gap, sensor ring integrity, and pickup condition during motor service.

FAQ

Q1: What is the difference between A06B-1405-B103 (Ai 3/10000) and A06B-1404-B103 (Ai 2/10000)?

Same flange, slick shaft, MZi sensor, rear exhaust, and 1,500–10,000 rpm range. The difference is power: Ai 2/10000 delivers 2.2 kW continuous / 3.7 kW S2-S3; Ai 3/10000 delivers 3.7 kW continuous / 5.5 kW S2-S3. The Ai 3/10000 is heavier (~47 kg vs the lighter Ai 2 frame). The spindle amplifier must be sized for 5.5 kW peak — the two motors are not interchangeable on the same amplifier without confirming current capacity.

Q2: What spindle amplifier is required?

FANUC Alpha i spindle amplifiers from the 6111, 6112, 6141, or 6142 series, sized for 5.5 kW peak output. Compatible CNC: Series 0i-B/C/D, 16i, 18i, 30i/31i/32i. The amplifier must carry the correct motor type parameter for the Ai 3/10000 and have the MZi sensor interface enabled.

Q3: Can the slick shaft be used with belt-drive arrangements?

Yes, provided the coupling hub clamping specification accounts for both transmitted torque and belt tension. Belt tension adds a radial load to the shaft — the coupling hub and bearing selection must be appropriate for the combined radial and torque loading at the application's belt tension and speed.

Q4: Which spindle CNC functions depend on the MZi sensor?

Oriented stop, Cs-axis (contour axis) operation, rigid tapping, and spindle orientation all require functioning MZi feedback. If the MZi fails or produces intermittent output, these functions alarm or fail to activate. Sensor air gap, pickup condition, and sensor ring integrity should be inspected during motor service.

Q5: What are the priority checks on a used A06B-1405-B103?

Check the slick shaft for fretting marks from improper coupling installation or removal and confirm no runout from hub damage. Inspect the MZi sensor assembly for mechanical damage and verify the sensor ring is intact. Measure three-phase winding resistance for balance and insulation resistance to earth. A bench run-up to 10,000 rpm with MZi signal monitoring and amplifier current tracking is the correct final check before production installation.