Mitsubishi HC-KFS23K-S49 AC Servo Motor 200W Keyed Shaft

Description

Product Introduction

The Mitsubishi HC-KFS23K-S49 is a 200W low-inertia AC servo motor designed for ultra-compact, high-response motion applications within the MELSERVO-J2S system family (matching MR-J2S-20A/B amplifiers). Operating at a rated speed of 3000 RPM, this motor delivers precise positioning capability thanks to its integrated 17-bit high-resolution absolute encoder (131,072 pulses/revolution).

The specific -S49 designation indicates a customized OEM shaft configuration featuring a keyway shaft with an integrated oil seal, protecting the front bearing against liquid and debris ingress. Designed for high-frequency start-stop cycles, the HC-KFS23K-S49 is a mainstay in small indexing tables, packaging machinery, and semiconductor pick-and-place equipment. When an active motor suffers insulation breakdown or encoder signal loss, swapping in a pre-tested direct replacement keeps production moving without mechanical adaptations.

Key Technical Specifications

Application Scenarios & The “Trench” Experience

We got hit with an urgent call at a high-speed electronics assembly plant where a precision pick-and-place feeder axis threw an E6 encoder communications error on an MR-J2S amplifier. Fluid mist from a nearby pneumatic oiler had seeped past a degraded front bearing seal over five years, destroying the optical encoder disc inside the motor housing. The machine line was completely down, holding up a major SMT production run. Attempting to fit a standard straight-shaft motor wasn’t an option because the driving belt pulley required an exact shaft keyway slot. Dropping in a bench-verified HC-KFS23K-S49 with an intact factory oil seal got the feeder recalibrated and running in under 30 minutes.

• Semiconductor & SMT Assembly: High-speed component placement heads requiring ultra-low inertia and high acceleration rates.
• Small Packaging Machinery: Material indexing and rotary pushers operating under tight cycle-time constraints.
• Lab Automation & Robotics: Precision liquid handling slides and small multi-axis articulated arms.
• Light CNC & Engraving: Auxiliary axis drives for high-precision tool positioning.

Transparency SOP: Quality Assurance & Testing

We don’t just ship motor housings out of a warehouse; every Mitsubishi HC-KFS23K-S49 goes through a comprehensive 5-step electromechanical verification SOP:

1. Inbound Physical & Mechanical Audit: Inspect the front shaft keyway, check radial/axial play on bearings, verify the oil seal lip integrity, and check connector pins for corrosion.
2. Winding & Megger Insulation Testing: Perform phase-to-phase resistance balance checks and 500V Megger insulation testing (phase-to-ground) to guarantee zero winding shorts or leakage.
3. Encoder Alignment & Handshake Audit: Connect the motor encoder to an MR-J2S test rig; verify communication handshakes, count data stability, and zero position feedback accuracy.
4. Full Dynamometer Test Run: Mount the motor to a test amplifier, driving it up to 4500 RPM to check for smooth rotation, thermal stability, low vibration, and acoustic noise levels.
5. Clean & Anti-Static Packaging: Clean the anodized housing, apply shaft protective covers, and wrap the unit in heavy ESD anti-static bubble packaging.

The Veteran’s Tech Trap Guide (Crucial Value-Add)

⚠️ Shaft Suffix Mismatches (-S49 vs Standard): Pay strict attention to the model suffix! A standard HC-KFS23 motor features a smooth straight shaft without a keyway or oil seal. Installing a standard straight shaft into a pulley setup designed for an -S49 keyed motor will lead to shaft slipping, ruined key seats, or premature bearing failure under radial loads.

❗ Encoder Connector Moisture Damage: The small plastic encoder and power connectors on the HC-KFS series can become brittle over time when exposed to heat and oil mist. Take extreme care when un-clipping the cable harness during replacement; forcing a stuck lock tab will snap the connector housing, leading to intermittent encoder communication alarms (E6 / E7 fault codes).

⚠️ Amp Matching Required: The HC-KFS23K-S49 is matched specifically for 200W MR-J2S series amplifiers (MR-J2S-20A/B). Do not attempt to drive this motor using newer MR-J3, MR-J4, or older MR-J2 drives without verifying parameter compatibility and motor cable wiring, as encoder communication protocols differ between generations.

HC-KFS23K-S49

Frequently Asked Questions (FAQ)

Q: Does the HC-KFS23K-S49 include an internal holding brake?

A: No. Models equipped with an internal electromagnetic holding brake carry the B designation (e.g., HC-KFS23BK-S49). Standard HC- models do not feature a built-in brake.

Q: Can I replace an HC-KFS23K-S49 with an HC-MFS23K-S49?

A: While both are 200W motors in the MR-J2S family, the HC-KFS is a low-inertia motor, whereas the HC-MFS is an ultra-low inertia motor. They have different rotor mass characteristics. Swapping them without retuning your drive gain parameters will result in mechanical oscillation or position overshoot.

Q: What does the 17-bit encoder resolution mean for machine accuracy?

A: A 17-bit absolute encoder provides 131,072 pulses per motor revolution. This high resolution allows the drive system to achieve micro-stepping accuracy, smooth velocity control at low speeds, and rapid positioning without mechanical hunting.

Q: Is the oil seal on the -S49 model user-replaceable?

A: The oil seal is integrated into the front endbell assembly. While experienced motor rebuilders can press in a replacement seal, replacing the complete front endbell or using a bench-verified replacement motor is recommended to maintain factory IP55 ratings.

Q: What warranty comes with this replacement servo motor?

A: Every Mitsubishi HC-KFS23K-S49 servo motor supplied comes backed by a full 12-month operational replacement warranty from our engineering test facility.