Delivering high-precision motion control in a low-inertia design, this 750W rotary servo motor is engineered for high-duty dynamic positioning applications. The Mitsubishi Electric HG-KR73B features an integrated electromagnetic brake and a high-resolution absolute encoder to ensure stable performance and safety under demanding industrial loads. It integrates seamlessly with MR-J4 series servo amplifiers to provide reliable velocity and position loop control.
Key Features
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Low Inertia Design: Optimized for high-frequency positioning cycles and rapid acceleration/deceleration.
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Electromagnetic Holding Brake: Built-in safety brake designed for vertical axis control and position retention during power-off states.
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High-Resolution Feedback: Equipped with a 22-bit absolute/incremental encoder providing 4,194,304 pulses per revolution for exceptional positioning accuracy.
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Robust Protection: IP65-rated totally enclosed, self-cooled construction suitable for challenging industrial environments.
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Flexible Integration: Fully compatible with CC-Link IE Field, SSCNET III/H, and general-purpose pulse/analog interfaces via compatible MR-J4 amplifiers.
Applications
- High-speed packaging machinery and labeling systems.
- Material handling systems and pick-and-place robotic gantries.
- Multi-axis CNC feed systems and textile machinery.
- Vertical lift axes requiring positive-lock holding brakes.
Technical Specifications
| Parameter |
Value |
| Manufacturer |
Mitsubishi Electric |
| Model Number |
HG-KR73B |
| Series |
HG-KR (Low Inertia, Small Capacity) |
| Rated Output |
0.75 kW (750 W) |
| Rated Speed |
3000 r/min |
| Maximum Speed |
6000 r/min |
| Rated Torque |
2.4 N.m |
| Maximum Torque |
8.4 N.m |
| Rated Current |
4.8 A |
| Maximum Current |
17 A |
| Voltage Class |
200V AC |
| Power Supply Capacity |
1.3 kVA |
| Moment of Inertia (J) |
1.37 x 10^-4 kg.m2 |
| Encoder Type |
22-bit Absolute/Incremental (4,194,304 pulses/rev) |
| Electromagnetic Brake |
Installed (Holding brake) |
| Thermal Class |
130 (B) |
| Protection Rating |
IP65 (excluding shaft-through portion) |
| Vibration Resistance |
49 m/s2 (X and Y directions) |
| Operating Temperature |
0 to 40 degC (non-freezing) |
| Net Weight |
3.8 kg |
| Shipping Weight (Calculated) |
5.0 kg |
Compatible Servo Amplifiers
| Interface Type |
Compatible Models |
| CC-Link IE Field Network |
MR-J4-70GF, MR-J4-70GF-RJ, MR-J4-70B-RJ010 |
| SSCNET III/H Interface |
MR-J4-70B, MR-J4-70B-RJ |
| Multi-Axis SSCNET III/H |
MR-J4W2-77B, MR-J4W2-1010B |
| General-Purpose (Pulse/Analog) |
MR-J4-70A, MR-J4-70A-RJ |
Empirical Engineering Insights
Alternative Models & Compatibility
The HG-KR73B serves as a direct upgrade path for legacy HF-KP73B series motors. When transitioning from HF-KP to HG-KR, ensure that the servo amplifier firmware is updated to support the 22-bit encoder resolution. Physical mounting dimensions (flange size and shaft diameter) remain identical, allowing for straightforward mechanical retrofits.
Application Pitfalls & Engineering Notes
The integrated electromagnetic brake on the HG-KR73B is strictly a holding brake and must never be used for dynamic deceleration or emergency stopping. Engaging the brake while the motor is rotating at high speed will cause rapid wear of the friction plates, leading to premature mechanical failure. For high-duty vertical axes, ensure the amplifier's brake output delay time (MBR signal) is correctly calibrated to prevent axis drop during power-up sequences.
Commissioning & Wiring Tips
Always use dedicated, double-shielded encoder cables to connect the HG-KR73B to the MR-J4 amplifier. High-frequency noise from the motor power lines can corrupt the 22-bit serial encoder data if run in the same conduit without proper shielding. Ensure the motor frame is grounded directly to the amplifier's ground terminal, and verify that the 24V DC power supply feeding the electromagnetic brake is regulated and isolated from the control logic power supply.
Installation Guidelines
CRITICAL WARNING:
Ensure all primary AC power sources are completely de-energized and locked out before attempting installation or maintenance. Wait at least 15 minutes for the servo amplifier's internal bus capacitors to fully discharge. Verify zero voltage across the bus terminals before handling motor power connections.
1
Mount the motor securely to a rigid, flat metal surface to facilitate heat dissipation. Ensure alignment of the motor shaft with the load coupling is within the specified radial (392 N) and thrust (147 N) limits to prevent bearing wear.
2
Connect the encoder cable and power cable to their respective receptacles. Ensure the connectors are fully seated and locked to maintain the IP65 environmental seal.
3
Wire the electromagnetic brake terminals to a dedicated 24V DC power source controlled by the amplifier's brake interlock (MBR) relay. Do not share this 24V line with inductive sensors or high-noise devices.
4
Perform a trial run at low speed without a mechanical load to verify correct rotation direction, encoder feedback, and holding brake release functionality before full system commissioning.