シュナイダー TeSys‑T (LTMR Series) Motor Management Controller — Application Scenarios
TeSys‑T is an intelligent motor‑protection & monitoring unit. Core values: comprehensive motor protection + I/O logic control + Modbus RTU bus for motor‑data & fault‑log upload. It targets three‑phase asynchronous motors requiring fine‑grained protection, remote monitoring and predictive maintenance. An external contactor is required for motor start‑stop.
製品の状態: Planned Obsolete, End‑of‑Life Date: Sep 30, 2026
シリーズ: TeSys‑T Intelligent Motor Management Unit, Modbus‑RS485 communication, 0.4‑8A motor circuit protection & 監視
- モデルコードの内訳
| 分野 | コード | 説明 |
| LTM | LTM | TeSys‑T motor management system series |
| R | R | Controller body |
| 8 | 8 | Rated current measuring range 0.4‑8 A |
| M | M | コミュニケーション: Modbus RTU (RS485) |
| F | F | Control supply: 100‑240 V AC |
| M | M | Terminal version M (standard terminals, 6から / 3DO relay outputs) |
- Main Electrical & Hardware Specifications
| アイテム | 価値 |
| Motor current measurement range | 0.4 … 8 A |
| 制御電源電圧 | 100‑240 V AC; operating tolerance: 93.5~264 V AC, 50/60 Hz |
| Logic Inputs (から) | 6‑channel AC‑type logic inputs; 0‑40 V = OFF state, 79‑264 V = ON state |
| Relay Outputs (する) | 3いいえ + 1NO+1NC fault relay; contact rating: AC250V/5A; DC30V/5A |
| 通信インターフェース | Modbus‑RTU RS485; dual RJ45 + terminal block port; ボーレート:1.2~19.2 kbit/s; アドレス範囲:1‑247 |
| Overall dimension (高さ×幅×奥行き) | 61 × 91 ×122.5 mm; 重さ:0.53 kg; DIN‑rail mounting |
| 使用周囲温度 | -20 ℃ … +60 ℃; 保管温度:‑40 ℃~+85 ℃; condensation prohibited |
| 定格絶縁電圧Ui | 690 V; pollution degree 3, overvoltage category III |
| 配線トルク | 0.5‑0.6 N·m; wire gauge:0.2‑2.5 mm² solid / フレキシブルケーブル |
Ⅲ. Built‑in Protection Functions
Thermal overload long‑time protection, locked‑rotor protection, 位相損失, phase unbalance, phase‑reversal, earth‑leakage protection
Recordable data: 障害イベント, 始動電流, operating hour counter, trip context, residual thermal capacity; pre‑alarm supported
拡大: with LTME expansion module for voltage measurement, power‑factor and load‑variation protection
- In‑depth Operating Principle
- Current acquisition: Built‑in 3‑phase current transformers measure motor true RMS current; integrated earth‑fault current detection.
- Thermal model: Embedded motor thermal‑memory algorithm simulates motor temperature rise for overload protection; cooling delay applied after tripping.
- I/O logic: 6 DIs receive external start/stop / local‑remote commands; 3 relay outputs drive contactor coils; fault relay provides alarm signal.
- Modbus bus: Upload current, thermal status, 故障コード, operating status; receive remote start‑stop and parameter modification commands.
- Local blue TEST/RESET push‑button: manual fault reset & local test; front‑panel LED indicators (POWER / 走る / ALARM / FAULT).
注記: This unit performs only protection & logic control. Main‑circuit contactor must be externally wired to build a complete motor starter circuit.
- Key Terminal Definitions (まとめ)
A1/A2: Controller power supply, 100‑240 VAC
C1‑C6: 6 logic input channels (から)
21‑24, 31‑34: 3 NO relay outputs (for contactor driving)
95‑96‑97: Fault relay, 1NO+1NC
Modbus: Dual‑port RS485 (RJ45 + 端子台), supports daisy‑chain networking
- アップグレード & 交換液 (Official TeSys‑Tera New‑generation Series)
TeSys‑Tera adopts separated architecture: controller body + external CT sensors. Direct‑pin‑to‑pin hardware replacement against legacy LTMR is not feasible; current‑sensing wiring modification is required.
| スキーム | 本体 | Current Sensor | 適用電流範囲 |
| Scheme 1 | LTMTMFM (Modbus, 100‑240 VAC/DC) | LTMTCTV3UT | 0.3‑3 A |
| Scheme 2 | LTMTMFM (Modbus, 100‑240 VAC/DC) | LTMTCTV25UT | 2.5‑25 A |
⚠ Upgrade Risks:
- Old LTMR integrates internal CT; new Tera uses external CT, cabinet wiring modification required.
- Modbus register mapping & parameters are not fully compatible; PLC program modification & commissioning are mandatory.
- I/O terminal layout is completely different; secondary‑wiring inside control cabinet must be reworked.
Ⅶ. 典型的なアプリケーションシナリオ
Three‑phase asynchronous motors such as pumps, ファン, コンプレッサーとコンベア; 水処理, 冶金, oil‑gas, 化学薬品, セメント産業; critical motor loops requiring PLC‑based bus access for motor‑protection status and fault‑log reading.
VIII. 選定メモ & Boundary Conditions
- Max measuring current 8 A; not applicable for motors with rated current higher than 8 A.
- DIs are AC‑voltage inputs, not dry‑contact inputs; external supply voltage is required for contact closure.
- Max relay output switching frequency: 2 Hz; unsuitable for high‑frequency cycling applications.
- Cabinet‑level protection is required for condensation‑prone or corrosive environments.
- Planned end‑of‑life: Sep‑30‑2026; new‑project designs shall adopt TeSys‑Tera preferentially.
- General‑process Industrial Equipment (最も一般的な)
- ファン & Pump Circuits
Circulating pumps, cooling pumps, sewage pumps, makeup‑water pumps, smoke‑exhaust fans, supply‑return fans, cooling‑tower fans.
価値観: 過負荷, locked‑rotor, phase‑loss & earth‑fault protection; upload running current, fault status and runtime; underload protection for pump dry‑run prevention.
産業: 空調設備, wastewater treatment, water‑works, building MEP.
- コンベヤ, belt feeders & screw feeders
ベルトコンベア, scraper conveyors, screw feeders, バケットエレベーター.
価値観: fast trip upon mechanical jamming; phase‑unbalance & earth‑fault protection; fault history for jam‑incident analysis; interlock‑logic support.
産業: 採掘, building materials, grain storage, logistics handling, chemical processing.
- コンプレッサー & refrigeration units
Screw air compressors, 冷凍コンプレッサー, process compressors.
価値観: prevent locked‑rotor / overload caused by liquid‑slugging; thermal‑model winding protection; upload motor status to PLC / SCADA via fieldbus.
- Water‑treatment & Municipal Industry (High‑volume TeSys‑T deployment)
Lift pumps, return‑flow pumps, agitator motors for chemical dosing, エアレーションブロワー, bar screens, scrapers.
Site features: large quantity of geographically distributed motors; remote monitoring of current & faults to reduce on‑site inspection; high incidence of phase‑loss & earth‑fault faults.
Typical architecture: Modbus‑RTU multi‑drop networking with PLC, aggregating motor‑protection data to SCADA host.
- 化学薬品 & 製薬産業
Reactor agitators, 循環ポンプ, metering pumps, material transfer pumps, 遠心分離機.
価値観:
- Earth‑leakage protection mitigating motor damage from process‑media leakage.
- Complete fault event log for process traceability and GMP compliance.
- Phase‑reversal protection to prevent reverse rotation after maintenance phase swapping.
注記: Controller body cannot be installed directly in hazardous explosive areas; explosion‑proof enclosures / contactors are required.
- 冶金, セメント & Building‑materials
Dust‑removal fans, 冷却ファン, distributing actuators, unloading drives, small roller‑table motors.
動作条件: heavy shock‑loading, 粉塵が多い; frequent locked‑rotor & phase‑loss events; combined thermal‑overload & fast locked‑rotor trip safeguards motor windings.
- Power‑plant Auxiliary Drives
Small auxiliary motors: 冷却ファン, lube‑oil pumps, seal‑water pumps.
価値観: critical auxiliary equipment; pre‑alarm & fault‑snapshot recording for root‑cause analysis after incidents.
- Logistics‑packaging & Plastics Machinery
コンベヤベルト, 撹拌者, フィーダー, auxiliary drives for small extruders.
利点: local / remote mode selection via DI; contactor‑coil driving via DO eliminates numerous intermediate relays.
✅ Selection Criteria for TeSys‑T
Choose LTMR if any condition below applies:
- Fieldbus communication required: read current, thermal‑capacity percentage, 営業時間, fault codes and fault snapshots.
- Valuable motors requiring full‑scope protection: 熱過負荷, locked‑rotor, phase‑loss, phase‑unbalance, phase‑reversal, earth‑fault, 負荷が低い.
- Local‑remote dual control mode plus complex interlock logic; reduce intermediate‑relay count.
- On‑site requirement for fault logging for post‑event troubleshooting.
- Multi‑motor centralized monitoring network connected to PLC / SCADA.
❌ Unsuitable Application Scenarios
- Only simple thermal‑relay protection needed without communication or fault logging: select low‑cost LRD thermal overload relays instead.
- Motor full‑load current far exceeds built‑in CT range (max integrated‑CT LTMR:100 あ). Use new‑generation TeSys‑Tera with external CT for higher‑current motors.
- High‑frequency motor cycling: relay DO max switching frequency 2 Hz; contact wear will accelerate.
- Intrinsically‑safe hazardous zones: controller body cannot mount inside hazardous area.
- Single‑phase‑motor protection: TeSys‑T targets three‑phase induction motors.
📌 Old‑vs‑New Generation Summary
遺産: LTMR series (例えば. LTMR08MFM), planned EOL Sep‑30‑2026, built‑in current transformers.
新しい: TeSys‑Tera (LTMT series), external‑CT architecture, broader current coverage; preferred for new‑project engineering.
Thermal‑Overload Protection Principle of Schneider TeSys‑T (LTMR)
TeSys‑T does not rely on physical bimetallic‑strip deformation like conventional thermal relays. It implements thermal‑overload protection via electronic thermal‑model (virtual‑motor thermal‑memory algorithm) + true‑RMS three‑phase‑current sampling.
- Hardware Acquisition Stage
- Built‑in three‑phase current transformers sample true RMS stator current (not simple peak values).
- Integrated earth‑fault‑current detection circuit.
- Analog‑current signals are digitized by MCU for periodic load‑current refresh.
For LTMR08MFM: internal CT measuring range:0.4‑8 A for direct stator‑loop current measurement.
- コア: Virtual‑motor Thermal‑Model (Thermal Memory)
The controller runs a mathematical model simulating motor‑winding heat accumulation and heat dissipation:
theta_{virtual} \propto \int(I^2 \cdot t)dt
Heat accumulation: thermal‑capacity percentage rises when operating current exceeds motor rated current.
放熱: thermal‑capacity percentage decreases during stop or light‑load operation, simulating natural motor cooling.
Two key configurable parameters drive model behaviour:
- Motor rated current Ir: set according to motor nameplate full‑load current.
- 旅行クラス (5/10/15/20/30), defines inverse‑time tripping characteristics.
📌 Thermal‑capacity percentage: internal variable 0‑100 %; overload trip triggers at 100 %. This value can be read via Modbus register.
Trip‑Class Definition
| 旅行クラス | Trip Time @7.2 × Ir | Typical Motor Application |
| Class 5 | 4‑5 s | Fast‑starting motors |
| Class 10 | 6‑10 s | Standard general‑purpose three‑phase induction motors (most‑used) |
| Class 15 | 9‑15 s | Heavy‑duty start‑load applications |
| Class 20 | 12‑20 s | High‑inertia heavy‑start motors |
| Class 30 | 18‑30 s | Long‑start‑time high‑inertia loads (例えば. 大型ファン) |
- Overload Handling for Two Typical Operating Conditions
① Continuous running overload (persistent over‑current)
Motor runs continuously with I>Ir; virtual thermal‑capacity accumulates until reaching 100 %. The controller outputs trip command, de‑energizes contactor‑coil relay outputs and stops the motor. Over‑load fault code plus fault snapshot (3‑phase current & thermal‑capacity at trip instant) are stored.
② Overload during motor start‑up (high‑magnitude starting inrush current)
Configured Trip‑Class permits short‑term high starting‑current without nuisance tripping; thermal‑model decays accumulated heat after start‑up completes.
⚠ Critical Feature: Thermal‑memory retention
After overload trip, virtual thermal‑capacity value does not reset immediately even if controller power supply remains alive. Model‑simulated cooling‑time must elapse or manual RESET is required.
Practical case: after motor trips from overload, windings remain hot. Instant reset & restart risks motor burnout. Thermal‑memory prevents premature restart and mimics real‑motor cooling behaviour.
- Pre‑alarm Function (Overload Early Warning)
Configurable thermal‑capacity threshold (e.g. 80 %). When virtual thermal‑capacity exceeds threshold, overload pre‑alarm activates without tripping. Warning signal can be transmitted via relay DO or Modbus for predictive maintenance before unplanned shutdown.
- 比較: Conventional Bimetallic Thermal Relay vs TeSys‑T LTMR Electronic Thermal‑model
| アイテム | Traditional LRD Bimetallic Thermal Relay | TeSys‑T LTMR Electronic Thermal‑model Overload Protection |
| 保護原則 | Bimetallic‑strip physical thermal deformation | Software‑based virtual thermal‑model with RMS‑current sampling |
| Thermal‑memory characteristic | Heat vanishes upon power‑loss; no thermal retention | Thermal‑memory can be retained upon power‑loss (設定可能) |
| Ambient‑temperature influence | Strong cabinet‑temperature‑dependent, notable deviation | Software temperature compensation; low environmental‑temperature sensitivity |
| Trip‑class setting | 修理済み (limited models support adjustment) | Software‑configurable Class 5‑30 |
| Data‑availability | No status output | Bus‑readable thermal‑capacity, fault snapshots, current measurements |
- Boundary‑conditions & 制限事項
- Overload protection protects motor‑winding thermal accumulation, not power cables; separate circuit‑breaker required for cable‑conductor protection.
- Phase‑loss / phase‑unbalance accelerates thermal‑model accumulation and advances trip threshold.
- Locked‑rotor and earth‑fault are independent protection functions, not part of overload logic.
- Adjust Trip‑Class if actual motor‑cooling condition deviates from internal model (例えば. forced‑air‑cooled motor).
- LTMR thermal‑model is designed for standard three‑phase induction motors. Direct reuse for VFD‑fed or special‑purpose motors is invalid; parameter tuning is mandatory.
- Fault‑reset Logic
- Auto‑reset: parameter‑enabled; reset occurs only after thermal‑model cools down to safe thermal‑capacity level.
- 手動リセット: local front‑panel RESET button, DI terminal reset signal, or Modbus‑bus reset command.
禁止された操作: repeated forced restarts before motor cools after thermal trip.
- 故障コード
Thermal‑overload trip fault code: OL1. Fault log stores timestamp, three‑phase current and thermal‑capacity percentage, retrievable via Modbus.
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