YASKAWA UTTSH-B24RH Servo Incremental Encoder

UTTSH: Yaskawa Sigma7 series encoder incrementale codice di serie (INC. ENCODER, incremental type)

B24: 24-risoluzione in bit (2500 P/R base, internal interpolation up to 16,000,000 impulsi/giro)

RH: Structural version, designed for rear mounting on SGM7G/SGM7A medium & large inertia servomotori

Distinction for the same series: UTTAH-B24RH is an absolute encoder, while UTTSH-B24RH is incremental. They share similar appearance and are NOT interchangeable.

Specifiche principali

Tipo: Encoder rotativo incrementale (INC)

Base line count: 2500 P/R

Internal interpolation: 16,000,000 impulsi/giro

Motori compatibili: SGM7G, SGM7A Yaskawa Sigma7 AC servo motors

Matching Drives: Sigma7 series (SGD7S/SGD7A)

Montaggio: Flange direct mount on motor rear end, coaxial structure

Alimentazione elettrica: DC5V (powered internally by servo motor)

Produzione: A/B/Z phase differential incremental signals

Example Applicable Motors

SGM7G-09AFC61, SGM7G-20AFA61, SGM7G-30AFC61, medium and high-power models of SGM7A series

Scenari applicativi tipici

Macchine utensili CNC, gantry equipment, macchine per lo stampaggio ad iniezione, macchine tessili, lithium battery equipment, robot external axes, high-precision transmission positioning.

Sintomi di guasto & Risoluzione dei problemi

Common alarms of damaged encoders (Sigma7 drive):

A.10 Encoder communication error

A.11 Encoder phase error

A.32 Position deviation excessive

Elenco di controllo per la risoluzione dei problemi:

1. Check if encoder fixing screws and shaft coupling (between motor shaft and encoder core) are loose
2. Inspect encoder connector pins for oxidation or pin retraction
3. Impacts, water ingress and oil contamination can easily shatter the code disc; only full encoder assembly replacement is viable
4. Dopo la sostituzione: Perform home position return after servo power-up. Incremental encoders lose position when power off.

Manutenzione & Precauzioni per la sostituzione

1. Never strike the code disc during encoder disassembly; glass code discs are fragile
2. Alignment marks must be matched properly. Misalignment directly triggers A.11 alarm and motor jitter
3. Distinguish UTTSH (incrementale) / UTTAH (assoluto). Wrong model installation results in malfunction
4. For second-hand units, test A/B phase waveforms and Z-phase zero point, confirm no cracks on code disc

Sostituzione & Spare Part Information

Original spare part: UTTSH-B24RH

Absolute version with identical appearance: UTTAH-B24RH (cannot directly replace UTTSH. Drive parameters need to switch to absolute mode, and the motor internal battery circuit differs)

Codice SA: 85437099 (Rotary Encoders)

Yaskawa Sigma7 (SGD7S/SGD7A) Parameter Setting Checklist after UTTSH-B24RH (24-bit Incremental Encoder) Sostituzione

Motori applicabili: SGM7G / SGM7A; Codificatore: UTTSH-B24RH【24-bit Serial Incremental Encoder】

Precondizione: Encoder mechanical alignment marks matched, fixing screws tightened, connector intact. Not UTTAH absolute encoder

Pre-operation (Before Power-on)

1. Spegnimento, confirm encoder alignment marks aligned, no stress or collision on code disc
2. Verify motor model matches the drive; motor nameplate code type F (24-bit incremental)
3. Connect PC with SigmaWin+, back up all original parameters first (obbligatorio)
4. Power on the drive and clear existing alarms
5. Core Encoder Type Parameters

UTTSH-B24RH is a 24-bit serial incremental encoder. The drive automatically recognizes 24-bit resolution upon power-up. No manual pulse count entry required, different from old external A/B encoders.

1. Alarm Clear & Reboot Procedure
2. Reset allarme: Fn002 (Alarm Reset)
3. After modifying Pn002, fully power down the drive, Aspettare 5 minutes then power on again for parameters to take effect
4. After power-up, Leggere [Motor Information] via SigmaWin+, confirm recognized as: 24bit Incremental Encoder

Recognition failure: A.10 encoder communication error, inspect connector, power supply and encoder body

III. Casa & Operation Related Parameters (Key for Incremental Encoder)

UTTSH incremental encoder loses home position on power loss, home return required every power-up

1. Trial Run Verification Steps (Item-by-item Check)
2. Funzionamento JOG (SigmaWin+ Fn003)

Normale: Motor rotates smoothly without jitter, no A.10/A.11

Abnormal A.11: Encoder alignment offset, power off and re-align marks

2. Monitor values: Un000 (Actual Speed), Un001 (Motor Position). Position value increases/decreases normally without jumping during rotation
3. Execute home return once, confirm Z-phase home mark captured correctly
4. Load trial operation, no A.32 excessive position deviation alarm
5. Fn Function Code Operation List

1. Insidie ​​​​comuni & Promemoria
2. ❌ Do NOT set Pn002 to 1/2: If original motor used UTTAH absolute encoder and replaced with UTTSH incremental, failure to change Pn002 directly triggers A.040 colpa
3. ❌ No need to set electronic gear numerator/denominator for 24-bit serial incremental encoder to match encoder pulses; drive auto-detects code disc resolution. Electronic gear only relates to mechanical reduction ratio and host pulse unit
4. A.11 phase error: 90% caused by misaligned encoder marks, not parameter issue. Prioritize mechanical reinstallation instead of modifying Pn080 blindly
5. No need to run absolute encoder zero reset (Fn013) after encoder replacement. Fn013 is invalid for UTTSH incremental encoder

VII. Final Documentation

1. Save parameters via Fn004
2. Export parameter backup file again, named: Motor Model+UTTSH-B24RH
3. Record on equipment: Encoder incrementale, home return required every power-up

Yaskawa Servo Motor Built-in Encoder Master List (Mainstream Sigma5 / Sigma7 Series)

Quick Naming Rule:

UTTxx = Sigma7 Series; UTSIx = Sigma5 Series

SH = Incremental Type; AH = Absolute Type

Middle Bxx = Resolution; Suffix RH/RK/FL/FK = Housing, flange and connector version. Most models with same prefix but different suffixes are NOT directly interchangeable

1. Sigma7 Series (SGM7G / SGM7A / SGM7J / SGM7P / SGM7D)【Focus: UTTSH-B24RH belongs here】

✅ Incremental Encoder UTTSH (24-bit Serial Incremental)

✅ Absolute Encoder UTTAH (24-bit Absolute, Alimentato a batteria)

New battery-less absolute for Sigma7 (B26 series): UTNAH-B26CX (26-bit battery-free absolute encoder for high-end SGM7G/A motors)

1. Sigma5 Series (SGMGH / SGMAH / SGMSH / SGMPSH) Older Generation, UTSIH / UTTIH

✅ Incremental UTSIH

✅ Absolute UTTIH

III. Sigma8 Latest Series (SGM8A/SGM8G)

Sigma8 encoders adopt revised prefixes, no longer UTTxx. New-generation 26-bit serial encoders paired with SGD8S drives. Not compatible with Sigma7 encoders

1. Quick Model Distinction Table (For Maintenance & Pezzi di ricambio)

1. Critical Replacement & Note sulla selezione
2. Same prefix with suffix RH / RK / FL are not universal: Different flange, connector and mounting hole layout. Cannot install even with identical resolution
3. UTTSH ≠ UTTAH: Similar external appearance, different hardware and drive parameters. Wrong assembly triggers A.040 / A.10 alarms
4. Sigma7 24-bit serial encoders do not require manual electronic gear setup for encoder pulse matching, drive auto-recognition applies. Same rule for old Sigma5 17bit. Only old standalone A/B encoders need manual configuration
5. SGM7D/SGM7E direct drive motors use dedicated built-in encoders, rarely sold separately in spare parts market
6. Obsolete Legacy Models (Sigma-II, Sigma-III, SGMAH/SGMPH)

LF series: LF-205A / LF-210 / LF-220, very old stock. Barely available as new original parts, only for legacy equipment repair