QTL 385 Series – Frameless Torque Motor
Water cooled frameless rotary torque motor with continuous torque from 407 Nm to 560 Nm, peak torque from 833 Nm to 1111 Nm and speeds up to 231 rpm. An integrated cooling ring suits high duty cycle applications, with a 385 mm outside diameter and 280 mm through bore.
Product Overview
| Motion Type | Rotary |
|---|---|
| Technology | Frameless Torque |
| Product Range | Torque Motors |
| Series | QTL 385 |
Key Performance Specs
- Continuous Torque Up To: 560 Nm
- Speed Up To: 231 rpm
- Outside Diameter: 385 mm
- Inside Diameter: 280 mm
Key Features
- Continuous torque range 407 Nm to 560 Nm
- Peak torque range 833 Nm to 1111 Nm
- Speed up to 231 rpm at 680 V dc
- Motor outside diameter 385 mm
- Motor inside diameter 280 mm
- Motor heights 85 mm and 105 mm
- Integrated cooling ring for high duty cycles
- PTC 1 kΩ and PT1000 thermal protection
- Frameless direct drive design
QTL 385 Series – Frameless Torque Motor
QTL 385 Series of Frameless Rotary Torque Motors
Introducing the QTL 385 Series frameless rotary torque motor by Tecnotion. Torque motors excel in their direct drive capabilities, eliminating the need for a transmission or gearbox. The rotor of the torque motor is securely attached directly to the driven part, reducing transmission losses and eliminating the cost and maintenance associated with additional components. With no contact between the rotor and stator, mechanical wear is eliminated, resulting in reduced maintenance and extended lifespan. These motors provide a high continuous torque throughout the entire rev-range. The required torque and available space play a role in determining the motor’s diameter and width. This allows for slim motors in height but large in diameter for applications such as axles and turntables, or compact yet high-torque motors with similar height and diameter dimensions.
Water Cooling for High Duty Cycles
The QTL 385 Series is fitted with an integrated cooling ring, allowing the motor to sustain higher continuous torque under demanding duty cycles. Liquid cooling draws heat away from the stator efficiently, keeping performance stable during prolonged high load operation and helping to extend motor life.
Applications for Torque Motors
Frameless torque motors find applications in a variety of industries and fields. They are commonly used in robotics, precision manufacturing, semiconductor manufacturing equipment, medical devices, aerospace, and defence systems. The compact design and high torque output make them ideal for applications where space is limited, yet high-performance and direct drive capabilities are required. Frameless torque motors are also well-suited for tasks that demand precise and accurate motion control, such as rotary tables, indexers, and positioning systems. Their versatility and reliability make them a preferred choice for demanding applications across multiple industries.
Product Specifications: QTL 385 Series – Frameless Torque Motor
| QTL 385 Series | Symbol | Unit | QTL-A 385-85 | QTL-A 385-105 |
| Winding type | I | I | ||
| Motor type, max voltage ph-ph (3-phase synchronous) | V ac rms (V dc) | 480 (680) | ||
| Ultimate torque (magnet @ 25°C) | Tu | Nm | 1026 | 1368 |
| Peak torque (magnet @ 25°C) | Tp | Nm | 833 | 1111 |
| Continuous torque (coil @ 100°C) | Tc | Nm | 407 | 560 |
| Stall torque (coil @ 100°C) | Ts | Nm | 288 | 396 |
| Maximum speed (@ Tc @ 680 V dc) | nmax | rpm | 231 | 164 |
| Motor torque constant (up to Ic) | Kt | Nm/Arms | 25.9 | 34.6 |
| Motor constant (coils @ 25°C) | Km | (Nm)²/W | 105.4 | 149.9 |
| Ultimate current (magnet @ 25°C) | Iu | Arms | 44.0 | 44.0 |
| Peak current (magnet @ 25°C) | Ip | Arms | 33.8 | 33.8 |
| Maximum continuous current (coils @ 100°C) | Ic | Arms | 15.7 | 16.2 |
| Stall current (coils @ 100°C) | Is | Arms | 11.1 | 11.5 |
| Back EMF phase-phase peak | Ke | V/krpm | 2217 | 2956 |
| Back EMF phase-phase rms | Ke | V/krpm | 1567 | 2090 |
| Coil resistance per phase (coils @ 25°C ex. cable) | R | Ω | 2.13 | 2.66 |
| Coil induction per phase (I < 0.6 Ip) | L | mH | 11.6 | 15.2 |
| Electrical time constant | τe | ms | 5.4 | 5.7 |
| Poles | Nmgn | nr | 50 | |
| Continuous power loss (coils @ 100°C) | Pc | W | 2044 | 2724 |
| Thermal resistance (coils to mount. sfc.) | Rth | °C/W | 0.039 | 0.029 |
| Thermal time constant | τth | s | 48 | 45 |
| Water cooling flow (for ΔT=3K) | Φw | l/min | 9.8 | 13.0 |
| Temperature cut-off / sensor | PTC 1 kΩ (3x) / PT1000 (3x) | |||
All specifications ±10%. Actual values depend on bus voltage. Values assume a mounting surface at 20°C with the motor driven at maximum continuous current. Thermal resistance is based on the given water flow and pressure.
Product Dimensions: QTL 385 Series – Frameless Torque Motor
| QTL 385 Mechanical | Symbol | Unit | QTL-A 385-85 | QTL-A 385-105 |
| Stator OD | ODs | mm | 385 | |
| Rotor ID | IDR | mm | 280 | |
| Motor height | Hmotor | mm | 85 | 105 |
| Lamination stack height | Hlam | mm | 60 | 80 |
| Rotor inertia | JR | kg·m² | 0.146 | 0.195 |
| Stator mass (excluding cables) | MS | kg | 12.75 | 17 |
| Rotor mass | MR | kg | 6.68 | 8.9 |
| Total mass (excluding cables) | MT | kg | 19.43 | 25.9 |
| Cable mass (all cables) | m | kg | 0.5 | |
| Cable type (power), length 2 m | d | mm (AWG) | 10.6 (13) | |
| Cable type (sensor), length 2 m | d | mm (AWG) | 8.9 (22) | |
Product Technical Drawings: QTL 385 Series – Frameless Torque Motor












