Mitsubishi HG-KN73BJ-S100 AC Servo Motor

HG-KN73BJ-S100 Down? Every Minute of Downtime Costs You Money — We Ship Same Day

Your line stopped. The MR-J4 drive is throwing an alarm. The encoder feedback is dead. You’ve already pulled the motor and confirmed it: HG-KN73BJ-S100 needs to go. We’ve been in that pit with you. This page exists for one reason — to get a verified, original Mitsubishi 750W servo motor on a plane to your facility before your production manager calls again.

We stock the Mitsubishi HG-KN73BJ-S100 in Xiamen, China. DHL Express to most destinations in 2–4 business days. No broker delays, no gray-market risk, no excuses.

⚡ URGENT REQUIREMENT? Contact: [email protected] | WhatsApp: +86 18359268345

Quick Technical Datasheet

Troubleshooting & Replacement Tips

Ten years of field calls taught me this: most HG-KN73BJ-S100 failures fall into three buckets. Know which one you’re dealing with before you even open the packing box.

1. Encoder Fault — AL.16 / AL.20 on MR-J4 Drive
This is the most common failure mode. The 22-bit battery-less absolute encoder uses an internal capacitor to retain position. If the motor sat unpowered for an extended period (months in storage, or after a catastrophic power event), the capacitor discharges and the encoder loses absolute reference. On power-up, the MR-J4 throws AL.16 (Encoder initial communication error) or AL.20 (Encoder normal communication error). Swapping the motor resolves this — but before you do, confirm the encoder cable (MR-ENCBL□M-A2-L) is not the culprit. Reseat both ends, check for bent pins at the motor connector, and verify the cable shield is grounded at the amplifier end only. If the alarm clears with a new cable, you saved yourself a motor swap.

2. Insulation Breakdown — AL.50 / Megger Test Failure
Coolant ingress through a degraded shaft seal is the primary cause on machining center axes. The IP65 rating holds under normal conditions, but repeated thermal cycling combined with coolant pressure eventually wicks moisture past the lip seal. Megger between any motor phase and frame: anything below 1 MΩ at 500 VDC is a failed motor. Do not attempt to dry and reinstall — insulation breakdown is progressive and will damage the MR-J4 output stage on the next thermal cycle.

3. Bearing Failure — Vibration / AL.37
Excessive radial load from misaligned couplings or overtightened timing belts accelerates bearing wear. AL.37 (Parameter error) sometimes masks a mechanical issue — run the MR-J4’s built-in vibration frequency display (Pr.PB13/PB14) before condemning the motor. If you see a resonance peak below 100 Hz that wasn’t there before, the bearings are going. Replace the motor; do not attempt field bearing replacement on a servo motor.

Replacement Checklist (HG-KN73BJ-S100 Swap):

• Power down the MR-J4 amplifier and wait for the charge LED to extinguish (minimum 15 minutes for capacitor discharge).
• Disconnect the encoder cable first, then the power cable. Label both.
• Remove the motor. Note the coupling alignment marks before disassembly.
• Install the new HG-KN73BJ-S100. Torque the flange bolts to the machine manufacturer’s spec — typically 4–6 N·m for M5 bolts on an 80 mm flange.
• Reconnect power cable, then encoder cable. Verify shield grounding.
• On first power-up, the MR-J4 will request an absolute position reset (AL.25). Use MR Configurator2 to execute the home position return or set the current position as home per your machine’s procedure.
• Run the auto-tuning sequence (one-touch tuning) before returning to production. The new motor’s inertia characteristics are identical to the original, so tuning parameters should require minimal adjustment — but verify.
• Check the S100 keyway engagement. Confirm the key is fully seated and the coupling set screw is torqued. A loose key under dynamic load will destroy the shaft within hours.

Reliability in Harsh Conditions

The HG-KN73BJ-S100 is not a lab instrument. It was designed for the floor — specifically for the kind of floor where coolant mist hangs in the air, ambient temperature swings 20°C between morning startup and afternoon peak production, and the machine hasn’t been cleaned since the last scheduled maintenance six months ago.

The IP65 enclosure seals the stator windings and encoder assembly against dust ingress and low-pressure water jets from any direction. The shaft seal is a double-lip design rated for continuous exposure to water-based coolants. The stator winding insulation is Class F (155°C thermal rating), providing substantial margin above the 40°C ambient operating limit — critical in enclosed machine cabinets where internal temperatures routinely exceed ambient by 20–30°C.

Vibration resistance is rated to 49 m/s² (5G) across the 10–500 Hz frequency range, covering the resonance bands of most machine tool spindle drives and conveyor systems. The rotor is dynamically balanced to G2.5 grade, which means the motor itself contributes negligible vibration to the mechanical system — any vibration you measure at the tool or end effector is coming from the load side, not the motor.

The battery-less absolute encoder eliminates one of the most common field failure points in servo systems: the encoder backup battery. Conventional absolute encoders require battery replacement every 3–5 years; a missed replacement means loss of absolute position on the next power cycle, requiring a full home position return on every axis. The HG-KN73BJ-S100’s capacitor-backed encoder retains position for approximately 100 hours without power — sufficient for any planned maintenance window.

Global Express Logistics

Our warehouse is located in Xiamen, Fujian Province, China — one of the country’s primary export hubs with direct access to Xiamen Gaoqi International Airport and the Port of Xiamen. This geography is not accidental. It means your urgent order moves fast.

Standard Express Process:

• Order Confirmed Before 14:00 CST: Same-day dispatch. The unit is packed, labeled, and handed to DHL or FedEx before the evening cutoff.
• DHL Express Worldwide: 2–3 business days to Europe, North America, Southeast Asia, and the Middle East. 3–5 business days to South America and Africa.
• FedEx International Priority: Available as an alternative carrier for destinations where FedEx has stronger coverage or the customer has a corporate account.
• Export Documentation: Commercial invoice, packing list, and certificate of origin prepared same day. HS Code 8501.52 declared for customs clearance. DDP (Delivered Duty Paid) terms available on request — we handle import duties so your receiving dock doesn’t get held up by a customs hold.
• Tracking: AWB number sent via email and WhatsApp within 2 hours of dispatch. Real-time tracking link included.
• Emergency Freight: For genuine production-critical situations, we can arrange next-flight-out courier on a case-by-case basis. Contact us directly on WhatsApp to discuss.

We have shipped to automotive plants in Germany, semiconductor fabs in Taiwan, food processing facilities in Australia, and paper mills in Brazil. The logistics process is the same every time: fast, documented, and traceable.

Contact Information

Production stopped? Don’t wait for a quote form to process.

📧 Email: [email protected]
📱 WhatsApp: +86 18359268345
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