Emergency: same day
For a line-down motor, where the fault and parts allow. WhatsApp us before you send it so the bench is kept free.
Fanuc · α, αi, β, βi Pulsecoders
Fanuc Pulsecoder repair: Alpha, Alpha i, Beta and Beta i encoders
Fanuc servo motors use serial Pulsecoders that report position, commutation and alarms to the amplifier. We test the count, commutation angle and status bits, repair or replace the Pulsecoder, align it at every pole pair and run the motor before return. Spindle sensors are covered too.
Repair turnaround you can plan around
Send a photo of the nameplate first. We confirm whether the motor is repairable, and the quote, the same working day.
Urgent: 3 working days
Repair, encoder alignment and test, counted from the day the motor reaches the bench and the quote is approved.
Standard: 7 working days
Full repair, encoder alignment, run test under load and a printed test report.
- Free repairability check from a nameplate photo
- Printed test report with every motor
- Written warranty, terms stated on every quotation
- Pickup can be arranged; parts that must be imported are quoted with their own timeline
01Models
Encoder models we test, repair and replace
| Pulsecoder | Counts per turn | Typical use |
|---|---|---|
| Pulsecoder A | 1,048,576 | Older serial motors |
| Pulsecoder B | 262,144 | Older serial motors |
| Pulsecoder B2 | 32,768 | Older serial motors |
| Pulsecoder C | 40,000 | Older serial motors |
| α I8, α A8 | 8,192 | α motors, 6-pole robot motors |
| α I64, α A64 | 65,536 | α series servo motors |
| α 1000A | 1,048,576 | α series, high resolution |
| αi I64i, αi A64i | 65,536 | αi series servo motors |
| αi 1000iI, αi 1000iA | 1,048,576 | αi series, high resolution |
| β I32B, β A32B | 32,768 | β series |
| β I64B, β A64B | 65,536 | β and βi series |
| β A128i | 131,072 | βi series |
| Absolute and incremental Pulsecoders with C1 to C8 | Various | Older motors and robots |
| Spindle sensors: MZ, gear sensor, position coder | ABZ | α and αi spindle motors |
I and A in the name stand for incremental and absolute. Absolute Pulsecoders keep the machine position with a battery in the amplifier or the cable.
02Faults
How these encoders usually fail
- Serial data errors from coolant entering past the shaft seal
- Count or pulse-miss errors from a contaminated or cracked disc
- Battery alarm and lost reference after the backup battery runs down
- Broken pins in the round JAE or HRS connector
- Pulsecoder replaced elsewhere without alignment, so the motor runs hot or trips
03Identify
Reading the label
The Pulsecoder model is on its label: α A64, αi A1000 and so on. The motor model on the nameplate, such as α 22/3000 or αiF 12/4000, tells us the pole count used for alignment.
04Motors
Motors fitted with these encoders
Fanuc α, αM, αC, αi, αiS, αiF, β and βi servo motors on CNC lathes, machining centres and presses; Fanuc robot axis motors; α and αi spindle motors with MZ or gear sensors; older Fanuc DC motors with resolver and tach.
05Service
What we do
Test and repair
Every check on the feedback test list, before and after repair.
Alignment
Commutation set to the rotor at every pole pair.
OpenMemory programming
Motor data written to a replacement encoder.
OpenReplacement
Matched encoder fitted, aligned and run tested.
Open06FAQ
Questions
Can a Fanuc Pulsecoder be repaired or only replaced?
Many faults are repairable: connector, board and memory problems, and contamination that has not scratched the disc. A damaged disc or sensor means replacement.
Does a new Pulsecoder need alignment?
Yes. It must be aligned to the rotor at every pole pair, or the motor will draw high current and lose torque.
What do SV0366, SV0367 and SV0368 alarms mean?
On most Fanuc controls they relate to the serial Pulsecoder: pulse miss, count miss and serial data error. See our encoder alarms guide.
Free downloads for your maintenance file
Printable one-page sheets from our bench. More on the resources page.
Servo motor encoder quick reference
Encoder families, interfaces, counts per revolution and the motors they sit on: Fanuc pulsecoders (alpha A64, A1000), Mitsubishi OBA/OSA, Yaskawa UTOPH, Tamagawa, Heidenhain ECN/EQN/ERN and SICK SKS/SRS/SRM.
PDF · 2 pages · 8 KB · free, no sign-up
Download PDFServo encoder alarm quick sheet
Common encoder and feedback alarms on Fanuc, Yaskawa, Mitsubishi and Siemens drives, what each usually points to, and what to check on the cable and connector first.
PDF · 1 page · 4 KB · free, no sign-up
Download PDF07Enquiry
Send the nameplate or encoder label
A clear photo of the motor nameplate and, if the cover is off, the encoder label is enough to start. We reply with whether it can be repaired and a quote.
Message received
Our team replies by email or WhatsApp, usually the same working day. For a line-down motor, WhatsApp +91 97866 22233.