To identify a FANUC servo motor, read the nameplate on the motor body. It shows the model name, such as aiS 8/4000, and the A06B specification number. Order by that full A06B number, including any suffix after the pound sign, not by the model name. Send us a photo of the plate and we will check our stock.
Where to Find the Nameplate
FANUC servo motors carry a nameplate on the housing. On a robot, the motors sit on the arm, so you may need to pull a cover or clean off grease and dirt before you can read it. On a CNC machine, the axis motors are often behind a way cover or a guard.
The plate carries a few things you need: the model name, the A06B specification number, and a serial number. It also lists electrical ratings. Get all of it. If the plate is worn or painted over, send whatever markings you can still read.
Why the Model Name Is Not Enough
The model name tells you the motor family and size. It does not tell you everything about the motor. Look at our own stock: under the aiS 8/4000 name we have motors listed as A06B-0235-B205, A06B-0235-B605 and A06B-0235-B005#S000. Same model name, three different part numbers.
Motors that share a name can still differ in things like the shaft, the brake or the feedback device on the back. That is why the part number differs. A motor that bolts up but does not match can leave you with a shaft that will not take your coupling, or a brake that is not there when the axis needs to hold. Our motor listings show the full A06B number, and you should order the same way.
Keep the Suffix
Some FANUC part numbers end with a pound sign and more characters, like the #S000 on one of our aiS 8/4000 servo motors. Treat the suffix as part of the number. Two motors that match everywhere except the suffix are not the same part on paper, and we will not tell you they are. If you are unsure whether a different suffix will work in your machine, the safe move is to match the number exactly.
What to Send Us
- A photo of the nameplate. Straight on, in focus, with the whole plate in the frame.
- The full A06B number. Typed out, including the suffix. It saves a round of back and forth.
- Where it came from. The robot model and controller, such as a FANUC M-20iA on an R-30iB Plus controller, or the CNC machine and its control. If it came off a FANUC R-2000 robot or another arm, the robot serial number helps too.
- Which axis. On a robot, tell us which joint. On a machine tool, which axis.
- How many. If you are stocking spares for a line of the same robots, tell us up front.
Motors, Amplifiers and Cables Go Together
A servo motor does not work alone. It runs off a servo amplifier in the controller or the machine cabinet, and it connects through power and feedback cables. If a motor failed, check the rest of the chain before you assume the motor is the only problem. Our post on understanding servo amplifiers explains how the drive side works, and we stock FANUC servo amplifiers by part number. Spindle motors on machine tools run off a separate spindle drive, and we have a FANUC spindle amplifier listed as well.
On the cable side, our post on robot connection cables covers what runs between the arm and the controller, and robot cable management covers keeping them alive on a moving arm. Replacement FANUC robot cable sets are in stock, along with an RP1 and RM1 extension cable set for the R-30iB Plus.
Robot or CNC
FANUC servo motors run on FANUC robots and on machine tools with FANUC CNC controls, like the FANUC 0i on the Samsung MCV 50 in our used vertical machining centers. The same rule applies on both: match the A06B number. We also carry FANUC CNC control units and MDI units, listed as FANUC 18i CNC parts and FANUC Series 160i parts, and the rest of our machine tools are under used CNC machines.
FANUC Servo Motors in Stock
- FANUC aiS 8/4000 servo motors: A06B-0235-B205 and A06B-0235-B605
- FANUC A06B-0162-B675 servo motors
For everything else, browse our FANUC robot parts category or the used FANUC robots on our floor.
Related Guides
- Reading FANUC servo amplifier part numbers
- Matching robot cable sets
- FANUC robot controllers explained
Spare Motors Sitting on a Shelf?
We buy surplus FANUC parts as well as complete robots and machines. Start with our sell surplus robot parts page, or ask about an industrial equipment appraisal for a larger lot.
Have the nameplate photo ready and call 586-752-0090, extension 1 for sales, or send it to our sales team.