The Yaskawa SGM7A-15AFA61 is a 1.5 kW low-inertia AC servo motor from the Sigma-7 series, designed for precise, high-speed positioning in modern automation systems. It combines a compact frame, high torque density, and a 24-bit high-resolution encoder, making it suitable for machine builders who need fast response and reliable accuracy in a 200 V class servo system.
1. Key Technical Data
| Item |
SGM7A-15AFA61 Specification |
| Series |
Yaskawa Sigma-7 low-inertia rotary servomotor |
| Rated output power |
1.5 kW |
| Rated line voltage |
200 V AC, 3-phase |
| Rated torque |
4.9 Nm |
| Peak (instantaneous) torque |
14.7 Nm |
| Rated speed |
3000 rpm |
| Maximum speed |
6000 rpm |
| Encoder type |
24-bit serial incremental encoder |
| Shaft type |
Straight shaft with key and tapped center |
| Motor moment of inertia |
2.0 × 10⁻⁴ kg·m² |
| Allowable load inertia |
Up to 10 × motor inertia |
| Protection class (typical set) |
IP67 when used with matching drive/cables |
| Approximate dimensions (W×H×D) |
100 × 160 × 202 mm |
| Approximate weight |
4.6 kg |
These values are based on published technical data for the SGM7A-15AFA61 within the Sigma-7 portfolio.
2. Role in the Sigma-7 Servo Family
Within the Sigma-7 family, the SGM7A-15AFA61 sits in the 1.5 kW power range and targets low-inertia, high-response applications. The low rotor inertia allows the motor to accelerate and decelerate quickly, which is essential for short indexing moves, rapid cycle machines, and applications where positioning time directly affects throughput. Yaskawa’s Sigma-7 concept focuses on increased efficiency, reduced heat generation, and more compact dimensions compared with earlier series, helping OEMs shrink machine footprints without sacrificing performance.
3. High-Resolution 24-bit Encoder
A core feature of the SGM7A-15AFA61 is its 24-bit serial incremental encoder. A 24-bit resolution means more than 16 million distinguishable positions per motor revolution, enabling very fine position control and smoother low-speed motion.
When combined with a compatible Sigma-7 servopack, this encoder resolution supports:
-
Tight positioning accuracy for pick-and-place and assembly applications
-
Smooth interpolation in CNC and motion control tasks
-
Improved speed stability at low rpm, useful in inspection and vision-guided systems
The serial encoder connection also reduces wiring complexity compared with older parallel encoder interfaces and helps maintain signal integrity over longer cable runs.
4. Torque, Speed, and Dynamic Performance
With a rated torque of 4.9 Nm and peak torque up to 14.7 Nm, the SGM7A-15AFA61 provides a solid balance of continuous load capability and short-term overload for rapid acceleration.
-
Rated speed 3000 rpm covers a wide range of standard mechanical transmission ratios and feed-screw applications.
-
Maximum speed 6000 rpm allows higher linear speeds or faster index times when the mechanical system permits.
The relatively low rotor inertia (around 2.0 × 10⁻⁴ kg·m²) supports aggressive tuning while still maintaining stability. This is particularly useful when the motor is driving moderate-inertia loads such as ball screws, small rotary tables, or compact belt axes.
5. Mechanical Design and Mounting Flexibility
The SGM7A-15AFA61 uses a straight shaft with key and tapped center, which is compatible with standard couplings, pulleys, and gearboxes.
Key mechanical points:
-
Flange size: 100 mm mounting dimension with a flange diameter around 115 mm, making it suitable for many compact servo gearboxes and machine frames.
-
Length and weight: Approximately 202 mm in depth and about 4.6 kg, providing a compact footprint relative to its torque rating.
-
Allowable load inertia: Up to ten times the motor’s own inertia, giving flexibility to drive moderate-inertia loads without excessively oversized gear reduction.
In many retrofit projects, the Sigma-7 SGM7A frame is designed to be compatible with previous Sigma-5 mounting patterns, simplifying upgrades while improving resolution and performance.
6. Electrical Characteristics and Protection
The motor is designed for 200 V class three-phase supplies and is typically paired with Sigma-7 servopacks such as the SGD7S series.
Important electrical aspects:
-
Rated power: 1.5 kW for continuous duty
-
Rated line current: around 9.3 A at 200 V in typical drive sets
-
Protection level: when used in a complete Sigma-7 system with appropriate cables and connectors, assemblies are typically specified to IP67 at the motor body, supporting use in environments where splashing liquids and dust are present.
This combination makes the SGM7A-15AFA61 suitable for many industrial sectors, from packaging and material handling to machine tools and electronics manufacturing.
7. Typical Application Areas
Thanks to its balance of power, speed, and precision, the SGM7A-15AFA61 is commonly used in applications such as:
| Application Type |
Typical Use of SGM7A-15AFA61 |
| Packaging machinery |
High-speed sealing jaws, rotary cutters, infeed axes |
| Electronics assembly |
Pick-and-place heads, small conveyors, indexing tables |
| Machine tools and CNC |
Auxiliary axes, tool changers, workpiece handling |
| Printing and labeling |
Registration rollers, unwind/rewind axes, label applicators |
| Inspection and test stands |
Precise motion for positioning test fixtures and sensors |
In each of these cases, the motor’s low inertia and 24-bit encoder resolution help achieve short cycle times with repeatable positioning, while the 1.5 kW rating gives enough margin for dynamic moves without oversizing the drive system.
8. Integration with Sigma-7 Servo Drives
When matched with Yaskawa Sigma-7 servo drives (Servopacks), the SGM7A-15AFA61 benefits from advanced control algorithms, autotuning functions, and a wide range of supported fieldbus interfaces. Sigma-7 drives can handle rotary, linear, and direct-drive motors within the same control platform, simplifying engineering for multi-axis machines.
Key system-level advantages include:
-
Fast tuning routines that use the high-resolution feedback to optimize response
-
Vibration suppression functions that help to reduce mechanical resonance in flexible machines
-
Built-in safety functions (depending on drive model) that simplify compliance with safety standards
9. Selection Considerations
When selecting the Yaskawa SGM7A-15AFA61, engineers typically consider:
-
Load inertia and gearing: With an allowable load inertia up to ten times the motor inertia, the motor works well with moderate-inertia loads using direct coupling or standard gear ratios.
-
Speed profile: For applications requiring frequent moves near 3000 rpm with occasional peaks to 6000 rpm, this model provides a comfortable margin.
-
Thermal performance: Sigma-7 motors are engineered for higher efficiency and lower heat generation than older series, which helps maintain performance in compact enclosures.
-
Mechanical envelope: The 100 mm flange and 202 mm depth must fit into the machine’s available space, especially in multi-axis arrangements.
10. Summary
The Yaskawa SGM7A-15AFA61 is a 1.5 kW, 200 V low-inertia servo motor that combines high-resolution feedback, strong torque performance, and a compact mechanical design. With a 24-bit serial incremental encoder, rated torque of 4.9 Nm, up to 14.7 Nm peak torque, and speeds up to 6000 rpm, it is well-suited to demanding motion control tasks in packaging, electronics, machine tools, and related industries.
When paired with Sigma-7 servo drives, the SGM7A-15AFA61 offers a robust, modern motion solution that supports precise positioning, fast cycle times, and long-term reliability in industrial automation equipment.
