Makerbase MKS SERVO57ES RS485 MB - NEMA 23 Motor Driver

Description

The MKS SERVO57ES RS485 MB stepper motor driver from Makerbase is designed to control two-phase NEMA 23 stepper motors in closed-loop systems. The module features an STM32F302CBT6 microcontroller, a Field-Oriented Control (FOC) algorithm and a 15-bit MT6826S magnetic encoder. The encoder monitors the actual motor shaft position, allowing the driver to detect deviations from the target position and adjust motor operation accordingly. Closed-loop control reduces the risk of missed steps and provides motion control for positioning mechanisms, CNC machines, robotics and industrial automation systems.

The MKS SERVO57ES RS485 MB operates with a supply voltage of 20 V to 48 V DC and supports an operating current range of 0 A to 5.2 A. The manufacturer specifies a maximum rotational speed of 3000 rpm. The FOC algorithm provides torque, speed and position regulation. The torque control loop operates at an update frequency of 20 kHz, while the speed and position control loops operate at 10 kHz. The driver supports relative and absolute position control, acceleration and deceleration profiles, and step subdivision interpolation up to 1/256. The control functions help reduce vibration and provide smooth motor movement.

The module provides STEP/DIR pulse control inputs and an RS485 communication interface. Pulse control allows the motor rotation direction and displacement to be specified using step signals. The driver supports Pulse/Direction control and dual-pulse CW/CCW control. The maximum input pulse frequency is 300 kHz. The STP, DIR and EN inputs feature optocoupler isolation, and the manufacturer specifies compatibility with control signal voltage levels from 3.3 V to 24 V. Isolation between the signal circuitry and the power stage facilitates integration with motion controllers and CNC machine control systems.

The RS485 interface with Modbus RTU protocol support provides serial communication with a host controller and enables configuration of motor operating parameters. The bus supports transmission rates from 9600 to 256000 bit/s and addressing for up to 255 slave devices. Broadcast and group addressing are also supported, allowing communication with multiple drivers within a single system. The RS485 A and B lines are available through the board's signal connectors. The interface supports the development of multi-axis motion control systems in which each drive has its own communication address.

The integrated 15-bit MT6826S magnetic encoder provides rotor position feedback for the closed-loop control algorithm. The driver features IN1 and IN2 inputs for travel limit signals, an ALM alarm output and a PEND output indicating that the target position has been reached. The ALM and PEND outputs use optocouplers and support voltages up to 35 V and currents up to 50 mA. An LED indicates the motor operating status and faults, including overcurrent, incorrect supply voltage, an open motor phase, positioning errors and encoder faults. The controller also supports restoring factory settings and updating its firmware.

The driver PCB measures 52.2 x 52.2 mm and is designed for mounting on the rear of a NEMA 23 stepper motor. The power stage uses HYG090ND06LS1C2 MOSFETs, while a four-position screw terminal block provides motor winding connections through the A-, A+, B- and B+ terminals. The included aluminum housing and silicone thermal pad help dissipate heat generated by the power components. The kit also contains a 6 x 3 mm radial magnet, screws, mounting spacers, an LED light guide and two 50 cm signal cables. The kit does not include a stepper motor. During installation, the magnet must be correctly aligned with the encoder, motor windings connected properly, and the supply voltage checked against the driver's requirements.

Features

• Technical specifications
  • Model: MKS SERVO57ES RS485 MB
  • Manufacturer: Makerbase
  • Device type: closed-loop stepper motor driver
  • Designed for: two-phase NEMA 23 stepper motors
  • Number of controlled motors: 1
  • Microcontroller: STM32F302CBT6
  • MOSFETs: HYG090ND06LS1C2
  • Magnetic encoder: MT6826S
  • Encoder resolution: 15 bits
  • Supply voltage: 20 V to 48 V DC
  • Operating current range: 0 A to 5.2 A
  • Maximum rotational speed: 3000 rpm
  • PCB dimensions: 52.2 x 52.2 mm
• Motor control
  • Control algorithm: FOC (Field-Oriented Control)
  • Closed-loop control with position feedback
  • Torque, speed and position regulation
  • Torque control loop update frequency: 20 kHz
  • Speed control loop update frequency: 10 kHz
  • Position control loop update frequency: 10 kHz
  • Relative and absolute position control
  • Pulse control modes: Pulse/Direction and CW/CCW
  • Maximum pulse signal frequency: 300 kHz
  • Step subdivision interpolation: up to 1/256
  • Acceleration and deceleration profile support
  • Motor stall and overload detection
  • Travel limit function support
• Interfaces and communication
  • STEP/DIR pulse control interface
  • RS485 communication interface
  • Communication protocol: Modbus RTU
  • RS485 transmission rates: 9600 to 256000 bit/s
  • Number of RS485 slave addresses: 255
  • Broadcast and group addressing support
  • RS485 connections: A, B
  • Pulse inputs: STP+, STP-, DIR+, DIR-
  • Enable input: EN+, EN-
  • Optocoupler isolation of pulse inputs
  • Control signal voltage levels: 3.3 V to 24 V
  • Multi-driver communication over a shared bus
• Connections, status indication and protection
  • Motor winding terminals: A-, A+, B-, B+
  • Travel limit inputs: IN1, IN2, IN COM
  • Alarm signal output: ALM+, ALM-
  • In-position signal output: PEND+, PEND-
  • Maximum ALM and PEND output voltage: 35 V
  • Maximum ALM and PEND output current: 50 mA
  • 5 V auxiliary power output
  • LED operating status and fault indication
  • Overcurrent fault indication
  • Open motor phase fault indication
  • Position and encoder fault indication
  • Overvoltage and undervoltage fault indication
  • Factory settings restoration
  • Firmware update support
  • Aluminum housing for improved heat dissipation

Kit Includes

• 1x Makerbase MKS SERVO57ES RS485 MB driver
• 1x MKS 57ES aluminum housing
• 1x radial magnet, 6 x 3 mm
• 1x silicone thermal pad
• 1x LED light guide, 3 x 9 mm
• 4x M3 x 15 mm hex socket head screws
• 3x M2 x 3 + 3 mm brass threaded spacers
• 3x CM2 x 3 x 4 cross-head thin-head machine screws, 304 stainless steel
• 1x HY 2.0 11-pin flat ribbon cable, 50 cm, 24 AWG, double-ended reverse
• 1x HY 2.0 12-pin cable, 50 cm, 24 AWG, double-ended reverse