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25kg.cm Wide Range Voltage Serial Bus Servo, High Precision And Large Torque, With Programmable 360 Degrees Magnetic Encoder
The ST3020 is a high-torque 25kg·cm serial bus servo with a 360° magnetic encoder, supporting 6–14V wide-range voltage input. It features an aluminium alloy ...
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The ST3020 is a high-torque 25kg·cm serial bus servo with a 360° magnetic encoder, supporting 6–14V wide-range voltage input. It features an aluminium alloy middle case, iron-core motor, and metal gearbox for reliable performance in demanding robotics applications.
The servo communicates via UART serial bus, allowing up to 253 servos to be controlled on a single channel. It supports multiple operating modes including angle servo mode (0–360°), speed closed-loop motor mode, and step mode. Two-way feedback provides real-time position, load, speed, voltage, current, and temperature data.
Key Features
- 25kg·cm Torque at 12V – High torque for demanding robotic joints and mechanisms
- 360° Magnetic Encoder – 12-bit precision with no friction or wear, extending servo lifetime
- Wide Voltage Input – 6–14V DC, compatible with 2S or 3S lithium batteries
- UART Serial Bus Control – Daisy-chain up to 253 servos on one channel
- Multiple Operating Modes – Angle servo, speed closed-loop motor, and step modes
- Two-Way Feedback – Real-time position, load, speed, voltage, current, and temperature
- Acceleration Control – Settable speed and acceleration for smoother motion
- One-Button Middle Position Calibration – 360° installation at any angle
- Multi-Loop Position Control – Up to 7.5 loops in both directions under default precision
- Aluminium Alloy Case – Improved heat tolerance and rigidity
- Metal Gearbox – High-precision copper and steel gears for low noise and stability
Specifications
- Torque: 25kg·cm (at 12V)
- Input Voltage: 6–14V DC
- Encoder: 12-bit magnetic (360°)
- Interface: UART serial bus
- Servo Wheels: T6061 aluminium alloy
Ideal For
- Quadruped and hexapod walking robots
- Robotic arms and grippers
- Pan-tilt mechanisms
- Projects requiring closed-loop servo control
Package Contents
- 1× ST3020 Serial Bus Servo
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- DC
- DC means direct current, where electricity flows in one constant direction, as supplied by batteries, USB ports and many plug-pack power supplies. When a product specifies DC, it runs from a DC supply rather than mains AC, so you need to provide the correct voltage and polarity.
- encoder
- An encoder is a sensor that converts the rotation or position of a shaft, knob or dial into electrical signals, reporting movement as incremental steps and direction, or as an absolute position. It is used to track how far something has turned, which matters for precise positioning, speed control, repeatable movement, or using a rotary knob as an input.
- servo
- A servo is a motor with built-in position control, usually told to move to a specific angle by a control signal. It matters when you need repeatable movement, such as steering, arms, flaps, or linkages, rather than continuous spinning.
- Tolerance
- Tolerance tells you how far the real resistance value may be from the printed value. A 1% resistor is useful when a circuit needs more predictable behaviour than a looser 5% or 10% part.
- Torque
- A twisting force that causes something to rotate, usually measured in newton-metres or kilogram-centimetres. It matters when choosing motors, servos, gears, and tools because higher torque is needed to lift heavier loads, turn larger wheels, or move mechanisms without stalling.
- UART
- UART is a simple asynchronous serial interface that sends data over separate transmit and receive wires, usually labelled TX and RX, with both ends set to the same baud rate. It is a common way for microcontrollers and other serial devices to exchange data.
Find this product in
Robotics & Motion
