SJ-2B4502TK (Mitsubishi Electric)

SJ-2B4502TK is a Mitsubishi Electric SJ-B series built-in AC spindle motor, used in medium-duty CNC machining centers. It belongs to the SJ-2B spindle motor family, designed for industrial cutting applications where higher torque and stable machining performance are required.

It is essentially a higher-load variant in the same 7.5 kW SJ-2B spindle class, sharing the same base structure as 4501TK but optimized for different coil/speed characteristics.

🔧 Verified specifications (official Mitsubishi data)

From Mitsubishi SJ-B series technical documentation:

Parameter	Value
Continuous rated output	7.5 kW
Short-time rated output	11 kW (30 min rating)
Acceleration/deceleration output	22 kW (standard class)
Actual accel/decel output	26.4 kW
Base speed	525 rpm (low-speed coil) / 1050 rpm (high-speed coil)
Maximum speed	10,000 rpm
Continuous torque	136 N·m / 68.2 N·m (coil dependent)
Short-time torque	200 N·m / 100 N·m
Rotor inertia	~0.042 kg·m²
Drive unit	MDS-D2-SP-200 / MDS-D2-SP-320 (depending on configuration)

🔧 Model code breakdown

Code part	Meaning
SJ	Mitsubishi spindle motor family
2B	SJ-B compact built-in spindle series
4502	7.5 kW class, higher-output / alternate coil configuration
TK	terminal / connector configuration type

So:

SJ-2B4502TK = 7.5 kW built-in spindle motor optimized for higher torque / alternate winding configuration

⚙️ How it differs from SJ-2B4501TK

Feature	4501TK	4502TK
Output class	7.5 kW	7.5 kW
Coil type	Standard	Alternate high-torque/high-speed configuration
Torque behavior	Balanced	Stronger low-speed torque option
Application	General machining	Heavier cutting / specific machine tuning

So the key idea:

Same power class, but 4502TK is tuned for different machining behavior (especially torque/speed tradeoff).

🏭 Typical applications

SJ-2B4502TK is used in:

vertical machining centers (VMCs)
general-purpose CNC milling machines
steel and cast iron machining
boring and drilling operations
production CNC equipment

It is selected when machines need:

⚖️ balanced power (7.5 kW class)
🧱 stable torque at low-to-mid speed
🎯 reliable continuous industrial machining
🔧 compatibility with Mitsubishi MDS-D2 spindle drives

⚖️ Position in Mitsubishi spindle lineup

Series	Role
SJ-2B	compact built-in spindle motors (older generation)
SJ-BG	modern high-speed integrated spindles
SJ-DG	high-torque cutting spindles
SJ-DL	external high-speed spindle motors

🧠 Simple explanation

SJ-2B4502TK is a 7.5 kW built-in CNC spindle motor designed for medium-duty machining, similar to 4501TK but with a different winding configuration that changes its torque and speed characteristics for specific machine requirements.

Mitsubishi M80 Built-IN Spindle Motor SJ-2B4502TK

Description