How to Select the Right Fanuc Servo Power Cable

A worn or wrongly specified power cable is one of the most common causes of nuisance alarms, insulation faults and downtime on Fanuc-controlled machines. Whether you are replacing a damaged cable on a running machine or wiring a rebuilt axis, taking five minutes to specify the cable correctly saves hours of troubleshooting later. This guide walks through the points we ask our own customers at JJ Automation when they need a Fanuc servo power cable.

1. Start with the motor and drive part numbers

Everything about the correct cable follows from the hardware at each end. Note down:

• Motor part number — on the Fanuc motor nameplate, usually beginning A06B- (for example A06B-0247-B100). This determines the motor-side connector size and pin count.
• Drive / amplifier part number — also A06B- series, on the front of the servo amplifier. This determines the amplifier-side termination: crimp terminals, a power connector, or lugs.
• Control series — 0, 10/11, 15, 16/18/21, 0i, 15i, 16i/18i/21i, 30i/31i/32i and so on. Older controls with red-cap MS connectors need different cable ends than the newer i-series amplifiers.

2. Identify the connector at each end

Fanuc servo power cables use a small number of connector families, and misidentifying them is the most frequent ordering mistake:

• MS-type circular connectors — threaded military-style connectors on older servo and spindle motors. Available in straight and 90-degree elbow versions; count the pins (4, up to 22-pin shells such as 18-10S or 22-22S) and note male or female inserts.
• Rectangular power connectors — the moulded 4- and 6-way blocks used on αi/βi series motors.
• Flying leads / lug terminations — many amplifier ends are simply stripped and crimped to the terminal block, so the cable is specified by conductor size and length.

If the cable uses an elbow (90°) motor connector, also note the exit direction of the cable when looking at the connector face — the elbow can be clocked in different orientations, and matching the original saves strain on the loom.

3. Fixed installation or cable track?

This decides the cable construction, not just the length:

• Stationary — routed once and clamped; standard PVC-insulated cable is fine.
• Cable track (drag chain) — moves with the axis every cycle. Use a high-flex construction rated for continuous flexing, otherwise conductors work-harden and break inside the insulation, giving intermittent open-phase alarms that are miserable to trace.

4. Length, conductor size and shielding

• Measure along the actual routing path, not point-to-point, and add slack for the connector service loop.
• Keep the conductor cross-section at or above the original — undersized power cores overheat and drop voltage on acceleration.
• Route power cables away from encoder/feedback cables, and always reconnect the shield and earth exactly as original. Many "encoder alarms" are really power-cable noise.

5. Fanuc power cables we stock

JJ Automation supplies genuine and compatible Fanuc power cables, connection cables and DC link bars from stock:

• F06B-0001-K012 — servo motor power cable, 22-22S connector
• F06B-0001-K008 — servo motor power cable, 18-10S connector
• Amplifier connection cables: A06B-6110-K801 (200 mm), A06B-6110-K802 (150 mm), A06B-6110-K803 (100 mm), A06B-6110-K804 (400 mm)
• DC link short bars: A06B-6078-K801 (90 mm), A06B-6078-K803 (64 mm), A06B-6078-K840 (154 mm), A06B-6078-K841 (300 mm), A06B-6078-K842 (150 mm)
• A660-2005-T779#160R0 — DC power cable for 30i/31i/32i automotive display units

Browse the full range in our Fanuc Power Cables collection, or see all Fanuc cables.

Not sure which cable you need?

Send us the motor and amplifier part numbers, a photo of both cable ends, the length and whether the cable runs in a drag chain — we will identify the correct cable for you the same day.