YASKAWA UTTSH-B24RH Servo Incremental Encoder

UTTSH: Yaskawa Sigma7 series インクリメンタルエンコーダ シリーズコード (INC. エンコーダー, incremental type)

B24: 24-ビット解像度 (2500 P/R base, internal interpolation up to 16,000,000 パルス/回転)

RH: Structural version, designed for rear mounting on SGM7G/SGM7A medium & large inertia サーボモーター

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

コア仕様

タイプ: Incremental rotary encoder (INC)

Base line count: 2500 P/R

Internal interpolation: 16,000,000 パルス/回転

Compatible Motors: SGM7G, SGM7A Yaskawa Sigma7 AC servo motors

一致するドライブ: Sigma7 series (SGD7S/SGD7A)

取り付け: Flange direct mount on motor rear end, coaxial structure

電源: DC5V (powered internally by servo motor)

出力: A/B/Z phase differential incremental signals

Example Applicable Motors

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

典型的なアプリケーションシナリオ

CNC工作機械, gantry equipment, 射出成形機, 繊維機械, リチウム電池設備, robot external axes, high-precision transmission positioning.

故障の症状 & トラブルシューティング

Common alarms of damaged encoders (Sigma7 drive):

A.10 Encoder communication error

A.11 Encoder phase error

A.32 Position deviation excessive

Troubleshooting Checklist:

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

メンテナンス & 交換時の注意事項

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

交換 & 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)

HSコード: 85437099 (Rotary Encoders)

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

適用モーター: SGM7G / SGM7A; エンコーダ: UTTSH-B24RH【24-bit Serial Incremental Encoder】

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

Pre-operation (Before Power-on)

電源を切る, confirm encoder alignment marks aligned, no stress or collision on code disc
Verify motor model matches the drive; motor nameplate code type F (24-bit incremental)
Connect PC with SigmaWin+, back up all original parameters first (mandatory)
Power on the drive and clear existing alarms
Core Encoder Type Parameters

Parameter No.	説明	Setting Value (UTTSH-B24RH Incremental)	備考
Pn002	Encoder Type Selection	Pn002 = □□□0	0=Incremental encoder; 1=Single-turn absolute; 2=Multi-turn absolute
Pn002	Encoder Type Selection	Pn002 = □□□0	⚠️ If previous encoder was UTTAH absolute, this must be set to 0, otherwise A.040 parameter abnormality occurs
Pn080	Motor Phase Sequence Selection	Keep original motor factory value, do not modify arbitrarily	Pn080 generally unchanged when replacing encoder; only check/tune phase sequence if A.11 phase alarm appears

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.

Alarm Clear & Reboot Procedure
Alarm reset: Fn002 (Alarm Reset)
After modifying Pn002, fully power down the drive, wait 5 minutes then power on again for parameters to take effect
After power-up, read [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. 家 & Operation Related Parameters (Key for Incremental Encoder)

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

Parameter No.	名前	備考
Pn200	Home Return Mode	Keep original setting from host controller; incremental mode cannot select “read absolute position directly after power on”
Pn50A / Pn50B	Input Terminal Definition	Retain backed-up original values, generally no modification
Pn100~Pn104	Gain Parameters	Load unchanged after encoder replacement, reuse old gain first. Re-run inertia identification if motor vibrates

Trial Run Verification Steps (Item-by-item Check)
JOG operation (SigmaWin+ Fn003)

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

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

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

Fn Code	関数	アプリケーションシナリオ
Fn002	Alarm Reset	Clear A10/A11 and other alarms
Fn003	JOG Operation	Low-speed test run after installation to inspect motor and encoder
Fn004	Parameter Save	Save parameters to drive flash memory after modification
Fn010	Inertia Identification	Re-auto-tune gain when motor vibrates (オプション)

よくある落とし穴 & Reminders
❌ 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 故障
❌ 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
A.11 phase error: 90% caused by misaligned encoder marks, not parameter issue. Prioritize mechanical reinstallation instead of modifying Pn080 blindly
No need to run absolute encoder zero reset (Fn013) after encoder replacement. Fn013 is invalid for UTTSH incremental encoder

Ⅶ. Final Documentation

Save parameters via Fn004
Export parameter backup file again, named: Motor Model+UTTSH-B24RH
Record on equipment: インクリメンタルエンコーダ, 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

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

✅ Incremental Encoder UTTSH (24-bit Serial Incremental)

Encoder Model	解決	適合モーター	備考
UTTSH-B24RH	24bit Incremental	SGM7G, SGM7A Medium & Large Inertia	Your target model, large flange side outlet connector
UTTSH-B24RK20	24bit Incremental	SGM7A/SGM7G Small Flange Version	Different connector position, cannot replace B24RH directly
UTTSH-B24RK50	24bit Incremental	High-power SGM7G Motors	Special for high-torque motors
UTTSH-B20RK	20bit Incremental	SGM7J / SGM7P Low Power	Low inertia flat motor

✅ Absolute Encoder UTTAH (24-bit Absolute, Battery-backed)

Encoder Model	解決	適合モーター	備考
UTTAH-B24RH	24bit Absolute	SGM7G, SGM7A	Almost identical appearance to UTTSH-B24RH, 直接交換できない
UTTAH-B24RT	24bit Absolute	High-power SGM7G	Terminal difference
UTTAH-B20FL	20bit Absolute	SGM7J / SGM7P	Low-power absolute motor
UTTAH-B20GL	20bit Absolute	SGM7J	Connector structural difference

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

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

✅ Incremental UTSIH

Encoder Model	解決	適合モーター
UTSIH-B17CA	17bit Incremental	Old Sigma5 SGMGH medium-large inertia
UTSIH-B17CK	17bit Incremental	SGMGH
UTSIH-B17CC	17bit Incremental	Low-power Sigma5 SGMAH

✅ Absolute UTTIH

Encoder Model	解決	適合モーター
UTTIH-B20FK	20bit Absolute	Sigma5 SGMGH
UTTIH-B20FN	20bit Absolute	SGMGH
UTTIH-B20TL	20bit Absolute	SGMGH

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

Quick Model Distinction Table (メンテナンス用 & スペアパーツ)

プレフィックス	世代	タイプ	Typical Resolution	Keywords
UTTSH	Sigma7	INC Incremental	24少し	Lose home on power off, Pn002=0
UTTAH	Sigma7	ABS Absolute	24少し	Battery-backed, retain position at power-off, Pn002=1
UTNAH	Sigma7	Battery-less Absolute	26少し	New design, no battery required
UTSIH	Sigma5	INC Incremental	17少し	Old Sigma5 motors
UTTIH	Sigma5	ABS Absolute	20少し	Old Sigma5 absolute

Critical Replacement & 選定メモ
Same prefix with suffix RH / RK / FL are not universal: Different flange, connector and mounting hole layout. Cannot install even with identical resolution
UTTSH ≠ UTTAH: Similar external appearance, different hardware and drive parameters. Wrong assembly triggers A.040 / A.10 alarms
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
SGM7D/SGM7E direct drive motors use dedicated built-in encoders, rarely sold separately in spare parts market
Obsolete Legacy Models (Sigma-II, Sigma-III, SGMAH/SGMPH)