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.
Incremental ABZ/UVW · Renco, BEI, Hengstler and others
Incremental servo encoder repair: Renco, BEI, Hengstler, Nemicon, Eltra, Baumer
Most older and many current servo motors use incremental encoders with A, B and Z channels and U, V and W commutation. They look simple, but a few degrees of phase error or one missing complement line is enough to stop a machine. We test every channel, repair or replace the encoder, and align the commutation to the rotor.
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
| Encoder | Typical motors |
|---|---|
| Renco RHS21D, RCH20, N-2300, N-3400, N-4200, N-5600 | Allen-Bradley MPL-H and N series, Reliance, Electrocraft |
| BEI H25, H25E | Baldor MTE, Gettys |
| Hengstler F14, S21 | Danaher and Kollmorgen AKM |
| Nemicon | Yaskawa USAEE |
| Eltra EH, EF80 | Powertech AX, Lafert B3081 |
| Baumer BHF and incremental | Sauer Danfoss TSL, Dietz DV |
| Encoder Products Company | Sumitomo FS |
| Thalheim | Lenze MDFK |
| Tamagawa ABZ/UVW | Motor Power Company T series, Applikon BAC, Lafert B630, Custom Servo MPM-892 |
| MTL Micro Encoder | Reliance |
| MicroE, DRC, Portescap E9, Nikki Denso E2-T3, Ono Sokki RP-446Z, Dietz and Global | Special and compact motors |
| Built-in ABZ/UVW encoders | Allen-Bradley TL and Y, Kollmorgen Goldline XT and BE1, Parker MPP, MPJ and MD3450, Giddings and Lewis, Exlar GSM, Axor SSA, Teknic, Vickers MT, Lenze MCS and MAS, Control Techniques NT and Emerson MGE, Pacific Scientific, ACM, MCG, Elwood Gettys SF, Linatrol HL, Aspen, Pactorq |
02Faults
How these encoders usually fail
- Phase between A and B drifted from 90°, so counts are lost at speed
- A complement line dead, so a differential receiver sees noise
- Missing or doubled index pulse
- UVW commutation edges off, so the motor runs hot or trips
- LED ageing, giving weak signals on long cables
03Identify
Reading the label
The encoder label gives the line count, for example 2,000 or 2,048 lines; multiply by four for counts per turn. Check whether the encoder has UVW commutation tracks and complement lines; this decides the test cable and the alignment method.
04Motors
Motors fitted with these encoders
Incremental encoders appear on almost every servo brand, from Allen-Bradley, Kollmorgen, Parker and Baldor to Lafert, Lenze, Exlar and Teknic. If your encoder is not listed, send the label.
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
How do you test an incremental encoder?
We count edges over several turns in both directions, measure A to B phase and pulse symmetry, check the index pulse, confirm every complement line, and check the UVW edges against the rotor.
What phase error is acceptable?
The ideal is 90° between A and B and 180° symmetry. Many makers allow about ±22°; we work to the encoder's own specification.
Can you replace an obsolete incremental encoder?
Usually, with the same or a compatible type of the same line count and commutation pattern, then aligned.
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 PDFEncoder alignment checklist
What to record before removing an encoder, the order of checks after refitting it, and the readings that tell you commutation is right before the motor goes back on the machine.
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.