One New Mitsubishi Servo Motor HC-SFS102BG1H HCSFS102BG1H HC-SFS102BG1H New In Box Factory Sealed

Mitsubishi HC-SFS102BG1H AC Servo Motor — 1 kW MELSERVO J2S with Electromagnetic Brake and High-Precision Planetary Gearhead, New

There's a category of motion control applications where a standard servo motor, however capable, simply cannot deliver the output shaft speed and torque characteristics the machine needs. Rotary indexing tables, robotic joints, material handling conveyors, and precision positioning stages all share one requirement: maximum torque at controlled low speed, without sacrificing positioning accuracy.

The Mitsubishi HC-SFS102BG1H is built for exactly that combination — a 1 kW MELSERVO J2S AC brushless servo motor with both a built-in electromagnetic brake and a high-precision planetary gearhead integrated at the factory.

This unit is offered new, in original Mitsubishi Electric packaging.

Three Things in One Housing

What makes the HC-SFS102BG1H distinctive is what the suffix characters bring together on a single motor assembly:

A 1 kW AC brushless servo motor — the HC-SFS102 base — with 17-bit absolute position encoding and IP65 environmental protection at its core.

An electromagnetic brake (B suffix) that holds the output shaft when power is removed, preventing uncontrolled motion on vertical or gravity-loaded axes.

A high-precision G1H planetary gearhead that steps down the motor's 2,000 rpm rated speed to a lower output speed while multiplying available torque by the gear ratio — delivering output torque levels that the bare motor cannot achieve on its own.

Factory integration of these three elements means precise mechanical alignment, a sealed assembly that maintains the motor's IP rating at the gearhead interface, and a single part number that covers all three functions without third-party component matching.

Base Motor Technical Specifications

The G1H Planetary Gearhead — General Industrial, High-Precision Class

Mitsubishi's gearhead designation system distinguishes between application classes. The G1 family covers planetary reduction gears designed for general industrial machinery — the broad category of automation equipment where reliable torque multiplication and reasonable backlash specifications meet practical cost and availability requirements.

The H suffix within the G1 family indicates the high-precision variant, offering tighter backlash control than standard G1 units.

In practice, planetary gearheads are the standard choice for servo-driven applications because of their coaxial design (input and output shafts are aligned), high torque density relative to physical size, and good efficiency compared to worm or helical gear alternatives.

The compact form factor integrates cleanly with the HC-SFS motor frame.

The available gear ratios for the G1H gearhead span multiple reduction steps — typical selections range from 1/3 through 1/45 depending on application speed and torque requirements. The specific ratio for a given unit is identified in the complete part number as ordered from Mitsubishi Electric.

What the Electromagnetic Brake Does Here

On a standard horizontal servo axis, losing power results in the motor coasting to a stop. On a vertical axis, an inclined axis, or any load with significant gravitational component, losing power without a holding mechanism allows the load to move under its own weight.

The spring-applied electromagnetic brake in the HC-SFS102BG1H engages automatically when the brake coil is de-energized — whether from a programmed stop, an E-stop, or an unplanned power failure.

The brake is released by applying voltage (typically 24 V DC from the control cabinet), and holds the shaft mechanically when that voltage is absent.

With the gearhead installed, the brake's holding effect is applied at the motor shaft, where the gear ratio multiplies it into a significantly higher holding torque at the output shaft.

This makes the combination particularly well-suited to vertical actuators, rotary tables that must hold position under load, and robot joints where mid-travel braking and at-rest holding are both required.

Where This Motor Combination Is Used

The HC-SFS102BG1H is the kind of motor that ends up in equipment where the design brief called for precision, reliability, and a compact geared drive package:

Rotary Indexing Tables — fixed-position indexing with high holding torque between index steps, where the brake secures the table between moves

Robotic Arm Joints — shoulder and elbow joints on industrial SCARA and articulated robots where gear reduction provides the torque leverage for load handling and the brake holds position when the drive is de-energized

Conveyor and Transfer Systems — indexing conveyor axes where controlled low-speed movement and positive position hold are both needed

Specialized Machining Equipment — rotary axis drives on turning centers and machining centers requiring gear-assisted torque at low output speeds

Winding and Tension Control — material winding applications where the gearhead provides the speed reduction and the brake prevents roll-off when stopped

Test and Measurement Equipment — precision positioning rigs where the gearhead provides stable low-speed resolution and the brake holds test position reliably

The 17-Bit Absolute Encoder Advantage

The encoder built into the HC-SFS102BG1H is a 17-bit absolute type, providing 131,072 unique position values per motor revolution.

This is a motor-shaft measurement — after the gearhead, the effective angular resolution at the output shaft is multiplied by the gear ratio, delivering extremely fine positional discrimination at the actual working point of the mechanism.

Absolute encoding means position data is retained through power cycles via battery backup in the servo amplifier.

At machine restart, every axis reports its position immediately — no reference return homing cycle required.

For indexing systems and robotic joints that must resume from known positions reliably, this capability is fundamental.

Compatible Drive Systems

The HC-SFS102BG1H is designed for Mitsubishi MELSERVO MR-J2S series amplifiers, specifically the MR-J2S-10A (analog command interface) or MR-J2S-10B (SSCNET high-speed serial command interface) for the 1 kW, 200 V class.

The amplifier must be configured appropriately for the motor's encoder type and the brake's electrical requirements. The brake typically requires a separate 24 V DC supply through the amplifier's brake release circuit or an external relay.

FAQ

Q1: What is the difference between the HC-SFS102B and the HC-SFS102BG1H?

Both share the same 1 kW base motor with electromagnetic brake and 17-bit absolute encoder.

The HC-SFS102B has a standard straight shaft output. The HC-SFS102BG1H adds a factory-integrated G1H high-precision planetary gearhead, stepping down the motor's rated 2,000 rpm to a lower output speed while multiplying available torque — making it suitable for applications that need high torque at controlled low speed.

Q2: What gear ratios are available for the HC-SFS102BG1H?

The G1H gearhead for the HC-SFS series is offered in several gear reduction ratios. The specific ratio is part of the complete Mitsubishi part number as configured. Common available ratios span from approximately 1/3 to 1/45, depending on the application's speed and torque requirements.

Confirm the exact ratio with the part number on the motor nameplate or with the Mitsubishi Electric product configuration documentation.

Q3: Which servo amplifier is compatible with the HC-SFS102BG1H?

This motor works with Mitsubishi MR-J2S-10A (analog command) or MR-J2S-10B (SSCNET digital command) amplifiers, rated for 1 kW in the 200 V AC class. The electromagnetic brake requires a 24 V DC brake release supply, typically provided through the amplifier's brake control output circuit.

Q4: Does adding the gearhead change how the encoder feedback works?

The encoder is mounted on the motor shaft, not the gearhead output shaft. Position feedback is measured at the motor end — the CNC or motion controller accounts for the gear ratio in its parameter settings to calculate actual output shaft position.

This is standard practice and is configured through the servo amplifier parameters during commissioning.

Q5: Is the HC-SFS102BG1H still being manufactured, and is new stock available?

The HC-SFS series belongs to Mitsubishi's MELSERVO J2S generation, which has been superseded by newer J4 and J5 series products for new machine designs.

However, new-in-box J2S motors remain available through industrial automation parts channels for maintenance, retrofit, and machine repair applications. Verify amplifier availability alongside the motor when planning long-term procurement.