Mitsubishi HF-KP43B MELSERVO J3 400W AC Servo Motor with Brake

Mitsubishi Electric MELSERVO J3 series HF‑KP43B is a low‑inertia, small‑capacity AC servo motor for high‑precision motion control applications requiring vertical axis holding or gravity‑loaded positioning. Rated output 400 W (0.4 kW) at 200 V AC class, 3‑phase. Built‑in 18‑bit absolute encoder (262,144 pulses/revolution) enables absolute position detection without homing at power‑up. Straight shaft design with built‑in electromagnetic holding brake. IP65 enclosure. 60 mm × 60 mm flange mounting. Natural cooling. This product is discontinued and available as a spare part for maintaining existing MELSERVO J3‑based systems.

Applications:

• Belt drive systems and textile machinery

• Pick‑and‑place mechanisms and automated assembly stations

• CNC machine tool feed axes and X‑Y tables

• Vertical axis lifting and gravity‑loaded positioning

• Semiconductor manufacturing and electronics assembly equipment

• Packaging machinery and labeling systems

Core Specifications:

• Rated output power: 400 W (0.4 kW)

• Rated torque: 1.3 N·m

• Maximum torque: 3.8 N·m (instantaneous)

• Rated current: 2.7 A

• Maximum current: 8.1 A

• Rated rotational speed: 3,000 rpm

• Maximum rotational speed: 6,000 rpm

• Permissible instantaneous speed: 6,900 rpm

• Moment of inertia (standard rotor): 0.42 × 10⁻⁴ kg·m²

• Moment of inertia (with brake): 0.50 × 10⁻⁴ kg·m²

Advanced Specifications:

• Encoder type: 18‑bit absolute encoder (262,144 pulses/revolution)

• Communication: Serial absolute/incremental encoder

• Power rate at continuous rated torque: 38.6 kW/s

• Recommended load inertia ratio: ≤ 22× motor inertia

• Insulation class: Class B

• Cooling method: Natural cooling (fanless)

• Protection rating: IP65 (excluding shaft‑through portion)

Electromagnetic Brake Specifications:

• Brake type: Spring‑operated holding brake (24 V DC)

• Rated voltage: 24 V DC (‑10%)

• Power consumption at 20 °C: 7.9 W

• Static friction torque: 1.3 N·m

• Release delay time: 0.03 s

• Engagement delay time: 0.02 s

• Permissible brake energy per stop: 22 J

• Permissible hourly brake energy: 220 J/h

• Brake cycles (lifetime): 20,000 operations

Environmental & Mechanical Specifications:

• Ambient operating temperature: 0 °C … 40 °C

• Storage temperature: –15 °C … 70 °C

• Ambient humidity: ≤ 80 % RH (non‑condensing)

• Vibration resistance: X 49 m/s², Y 49 m/s²

• Maximum radial load: 245 N

• Maximum axial load: 98 N

• Dimensions (W × H × D): 63 mm × 63 mm × 138 mm (approx.)

• Weight (with brake): approx. 1.6 – 2.1 kg

System Integration:

• This servo motor belongs to the Mitsubishi Electric MELSERVO J3 series.

• Compatible servo amplifiers: MR‑J3‑40A (pulse train interface), MR‑J3‑40B (SSCNET III/H interface), MR‑J3‑40A1 (pulse train, drive command), MR‑J3‑40B1 (SSCNET III/H).

• For absolute position retention during power‑off, no external battery is required for encoder data retention (18‑bit absolute encoder with battery backup).

• The built‑in electromagnetic brake requires an external 24 V DC power supply. Brake terminals (B1/B2) are non‑polarised. Do not use the 24 V DC interface power supply for the electromagnetic brake.

• For detailed installation, wiring, and parameter setting, refer to the MELSERVO‑J3 Instruction Manual.

Product Status:
Discontinued as of May 1, 2019. Available as a spare part for maintaining existing MELSERVO J3‑based systems while stocks permit. For new installations, use the recommended successor (HG‑KR43B).

Recommended Replacement:

• HG‑KR43B: MELSERVO‑J4 series 400 W low‑inertia AC servo motor with 22‑bit absolute encoder (4,194,304 pulses/revolution), IP65, straight shaft with built‑in electromagnetic brake, 3000 rpm, 1.3 N·m rated torque. Compatible with MR‑J4‑40B (SSCNET III/H), MR‑J4‑40A (pulse train), and MR‑J4‑40GF (fully closed loop) servo amplifiers.

Related Products:

• MR‑J3‑40B – J3 series SSCNET III/H amplifier, 400 W, for multi‑axis synchronization

• MR‑J3‑40A – J3 series pulse train amplifier, 400 W, universal interface

• HG‑KR43B – Recommended replacement (J4 series, 400 W, with brake, 22‑bit encoder)

• MR‑PWS1CBL2M‑A1 – Power cable, 2 m (standard bending life)

• MR‑J3ENCBL2M‑A1 – Encoder cable, 2 m (standard bending life)

• MR‑BAT6V1SET – Battery for absolute encoder (for absolute position retention)