One New Mitsubishi Servo Motor HC-SFS53K HCSFS53K Fast Delivery Lots Of Stock Best Price

Mitsubishi HC-SFS53K AC Servo Motor — 500W MELSERVO J2S 3,000 rpm Keyed Shaft | New In Box | Fast Delivery | In Stock

There are installations where a clamp-style coupling works perfectly, and there are installations where it doesn't — where the transmitted torque, shock load, or keyway requirement in the driven component makes a keyed shaft the correct mechanical interface.

That is precisely what the HC-SFS53K provides: the same proven 500W / 3,000 rpm HC-SFS53 servo motor with a factory-machined keyway on the output shaft. New, sealed in original Mitsubishi Electric packaging, and in stock for immediate dispatch.

Technical Specifications

The Keyed Shaft — When and Why It Matters

The distinction between a standard straight shaft and a keyed shaft comes down to one question: how is the torque actually transmitted from the motor shaft to the driven component?

A plain straight shaft relies entirely on the coupling clamp force — typically a split-hub clamp coupling or tapered bushing — to grip the shaft and prevent any rotational slippage. For many servo applications, that is perfectly adequate.

But there are cases where it is not. Pulleys, sprockets, and gear hubs that were originally designed for keyed-shaft motors have a keyway bore as their standard interface. Retrofit installations replacing worn or failed motors must match the original shaft configuration. High-shock loads — from indexing mechanisms, sudden braking, or aggressive acceleration profiles — place higher demands on the coupling interface than a clamp alone can reliably sustain over time.

The HC-SFS53K adds a factory-machined parallel key and keyway to the shaft, providing a positive mechanical interlock between the shaft and the driven hub.

The key transmits torque by direct mechanical engagement rather than relying solely on friction, which is the right choice for the applications listed above.

500W at 3,000 rpm — The Speed-Optimized Side of the HC-SFS 500W Family

Within the HC-SFS 500W lineup, Mitsubishi offers two rated speed options. The HC-SFS52K runs at 2,000 rpm with higher rated torque (2.39 Nm); the HC-SFS53K runs at 3,000 rpm with 1.59 Nm. The power output is nominally the same — the difference is how that power is delivered across the speed range.

The 3,000 rpm variant is the better choice when the machine axis runs frequently at higher speeds, when faster rapid traverse reduces cycle time, or when the gear ratio at the mechanism calls for higher input speed at lower output speed. On CNC machine tool axes, conveyor systems, and rotary table drives, this speed advantage translates directly into shorter non-cutting time per part.

17-Bit Absolute Encoder — Position Always Known

Every HC-SFS53K leaves the factory with a 17-bit absolute optical encoder integrated into the motor body — 131,072 discrete positions per shaft revolution, transmitted via Mitsubishi's high-speed serial protocol to the servo amplifier.

Being absolute means the motor's shaft position is retained through power-off cycles when the amplifier battery is installed.

Machine startup does not require a reference return homing sequence.

For multi-axis machines where homing runs on all axes sequentially before the machine is ready, eliminating that process saves measurable time on every power cycle across the machine's service life. The encoder also provides the feedback resolution needed for precise interpolated motion and fine positioning repeatability in demanding applications.

Oil Seal and IP65 — Built for the Shop Floor

Alongside the keyed shaft, the HC-SFS53K carries the same factory-installed oil seal at the drive-end shaft bore as the rest of the HC-SFS53 family. On active machine tools, coolant mist, cutting fluid, and fine swarf particulates are present in the air around the motor — the oil seal closes the shaft penetration as the most direct contamination path into the bearing and encoder cavity.

The IP65-rated housing extends that protection to the full motor body: complete dust exclusion and resistance to directed water jets from any angle. No additional environmental enclosure is needed for standard machine tool or industrial automation installations.

This protection level is standard across the HC-SFS series and is one of the reasons these motors are a common first-choice specification for CNC machining and production equipment.

Compatible Servo Amplifiers

The HC-SFS53K is mechanically a variant of the HC-SFS53 — the amplifier pairing is identical. The correct drives are the MR-J2S-60A (analog speed/torque command or pulse-train position command) or MR-J2S-60B (SSCNET digital network interface for multi-axis coordinated control via Mitsubishi motion controllers). The MR-J2S-60CP with built-in positioning function is also supported for standalone single-axis positioning systems without an external motion controller.

Amplifier selection depends on the control architecture: pulse-train from a PLC or CNC for the A-type, or SSCNET fiber-optic network from an A-series or Q-series motion module for the B-type.

Application Fit

The HC-SFS53K is specified wherever the HC-SFS53's performance characteristics are required and the keyed shaft interface is either needed or preferred:

CNC machine tool feed axes — X, Y, Z axes on smaller vertical and horizontal machining centers, particularly where the ballscrew coupling hub is designed for a keyed shaft

CNC turning centers — Z and X feed axes, especially in retrofits replacing older keyed-shaft servo motors where the coupling component already has a keyway bore

Rotary tables and 4th axis drives — where the worm gear input shaft or drive coupling accepts a keyed motor shaft as the standard interface

Conveyor and material handling — drives where a timing pulley or sprocket with a keyway bore is coupled directly to the motor shaft

Gearhead-coupled installations — where an intermediate gearbox accepts a keyed input shaft, providing a positive mechanical lock for high-shock or reversing load duty cycles

Industrial robot joints — forearm and elbow axis drives on medium-payload articulated and SCARA robots where keyed coupling is specified in the original design

HC-SFS53 Variant Overview

The HC-SFS53 base motor covers four mechanical configurations, all sharing identical electrical specifications:

• HC-SFS53 — straight shaft, no brake
• HC-SFS53B — straight shaft, with spring-applied electromagnetic brake
• HC-SFS53K — keyed shaft, no brake (this listing)
• HC-SFS53BK — keyed shaft, with electromagnetic brake

All variants deliver 500W at 3,000 rpm, 1.59 Nm rated torque, 17-bit absolute encoder, IP65 housing, and 130 × 130 mm flange. The selection between variants is purely a matter of mechanical interface and safety hold requirements — the servo performance characteristics are identical across all four.

FAQ

Q1: What is the difference between the HC-SFS53 and HC-SFS53K?

The only difference is the shaft. The HC-SFS53 has a plain straight shaft; the HC-SFS53K has the same straight shaft with a factory-machined parallel keyway and key included. All motor specifications — output power, torque, speed, encoder, flange, IP rating — are identical.

Choose the K variant when the driven component (pulley, sprocket, gear hub, or gearbox input) requires a keyed shaft interface.

Q2: Which servo amplifier is compatible with the HC-SFS53K?

The HC-SFS53K pairs with the MR-J2S-60A (analog/pulse-train interface) or MR-J2S-60B (SSCNET multi-axis network interface) servo amplifiers, both rated at 600W within the MELSERVO J2S platform. The MR-J2S-60CP is also compatible for standalone positioning applications.

All three amplifiers handle the motor identically — the K suffix does not affect amplifier compatibility.

Q3: Does the keyed shaft affect the IP65 protection rating?

The IP65 rating applies to the motor body, excluding the shaft end and connector interface — which is standard across the entire HC-SFS series regardless of shaft type. The keyway itself does not reduce the motor's environmental protection.

The factory-fitted oil seal at the shaft bore provides the primary contamination barrier at the shaft penetration, and this is identical on both the standard and K variants.

Q4: Does the HC-SFS53K support absolute position retention through a power-off cycle?

Yes. The 17-bit encoder is an absolute type. With a Mitsubishi A6BAT battery installed in the servo amplifier, multi-turn position data is stored when mains power is removed.

At the next startup, all axis positions are immediately available with no homing or reference return required.

Q5: What is the current-generation replacement for the HC-SFS53K?

The HC-SFS series is part of Mitsubishi's discontinued MELSERVO J2S generation. The nearest current-generation equivalent in Mitsubishi's active lineup is the HG-JR53 (MELSERVO J4 series) — same 500W, 3,000 rpm, oil seal, with a higher-resolution 22-bit encoder and IP67 rating, but requiring J4-series amplifiers.

For existing J2S platform machines, the HC-SFS53K remains the correct maintenance and spare parts specification.