Description
SJ-DG7.5/120-05T is a Mitsubishi Electric SJ-DG series high-output, high-torque CNC spindle motor designed for aggressive machining applications that require fast spindle acceleration and high dynamic response.
It belongs to Mitsubishi’s SJ-DG high-performance spindle family, which improves acceleration/deceleration torque compared with the standard SJ-D series.
🔧 Key specifications (SJ-DG7.5/120-05T)
| Parameter | Value |
|---|---|
| Series | SJ-DG |
| Type | High-output AC spindle motor |
| Continuous rated output | 5.5 kW |
| Short-time rated output | 11 kW (25% ED) |
| Standard accel/decel output | 11 kW |
| Actual accel/decel output | 13.2 kW |
| Base speed | 1500 rpm |
| Maximum speed | 12,000 rpm |
| Continuous rated torque | 35.0 N·m |
| Frame number | A112 |
| Shaft diameter | Ø32 mm |
| Flange size | 204 mm square |
| Total length (excluding shaft) | 439 mm |
| Approx. mass | 50 kg |
| Compatible spindle drive | MDS-D2-SP-160 |
| Protection class | IP54 (shaft area excluded) |
| Heat resistance class | Class F (155°C) |
These values come directly from Mitsubishi’s official MDS spindle system specification manuals.
⚙️ What the “05T” means
| Code part | Meaning |
|---|---|
| SJ-DG | High-output / high-torque spindle motor series |
| 7.5 | Power class |
| /120 | 120-frame spindle family |
| 05 | Higher-capacity specification variant |
| T | Through-spindle / hollow-shaft compatible configuration |
The “T” variant is commonly used in:
- through-tool coolant spindle systems
- compact spindle cartridge assemblies
- high-speed machining centers
⚙️ How SJ-DG differs from standard SJ-D
Standard SJ-D
- General-purpose spindle motor
- Balanced efficiency and cutting performance
- Conventional CNC machining
SJ-DG
- Higher acceleration/deceleration capability
- Stronger transient torque
- Better spindle response
- Optimized for aggressive cutting cycles
Mitsubishi specifically notes that the SJ-DG series improves “output and torque acceleration/deceleration characteristics.”
🏭 Typical applications
Used in:
- high-speed machining centers
- mold & die machining
- precision milling systems
- high-response spindle applications
- CNC systems needing rapid spindle acceleration
⚠️ Important notes
- Not a servo positioning motor
- Not a linear motor
- Requires Mitsubishi spindle drive electronics
- Cooling and bearing maintenance are critical at 12,000 rpm
- Must be matched correctly with Mitsubishi MDS spindle amplifiers
🧠 Simple explanation
SJ-DG7.5/120-05T is a high-dynamic CNC spindle motor capable of 12,000 rpm with strong acceleration performance and high transient torque, designed for fast and aggressive precision machining.