MOONS' SR2 2-Phase Stepping Motor Drive User Manual

1 Introduction

Thank you for selecting a MOONS' motor drive. We hope our dedication to performance, quality and economy will make your motion control project successful.

If there's anything we can do to improve our products or help you use them better, please call (86)21-52634688 or fax (86)21-62968682. You can also email info@moons.com.cn.

1.1 Overview

The SR2 drive is a cost-effective, high-performance 2-phase stepping drive, designed based on PID current control technology, with high torque, low noise, and low vibration. Users can select the running current and microstep resolution using a piano switch. The objective is to provide a drive that is cheaper but with better performance, especially for the low-cost and high-quality market.

1.2 Features

• Power Supply: SR2: 12 to 48 VDC
• Output Power: Max 2.2 Amps Peak
• Current Control: Advanced digital current control provides excellent high-speed torque.
• Microstep Resolution: Position Switch selectable, 16 settings: 200, 400, 800, 1600, 3200, 6400, 12800, 25600, 1000, 2000, 4000, 5000, 8000, 10000, 20000, 25000 step/rev.
• Speed Range: Up to 3000rpm.
• Anti Resonance: Raises the system-damping ratio to eliminate midrange instability and allow stable operation throughout the speed range of the motor.
• Auto Setup: Measures motor parameters and configures motor current control and anti-resonance gain settings.
• Microstep Emulation: Performs high-resolution stepping by synthesizing coarse steps into fine micro-steps.
• Control Modes: Step & Direction or CW/CCW model.
• Input Digital Filters: 150KHz or 2 MHz Digital Filter for high-speed inputs.
• Idle Current: Position Switch selectable, automatic 50% or 90% idle running current after 1s if the motor needn't move.
• Self Test: Position Switch selectable; the drive will perform a 2 rev, 1RPS, CW/CCW move test.
• Load Inertia: Position Switch selects the High or Low load inertia for smooth motion.
• Signal Smoothing: Position Switch selectable; firmware-configurable filtering reduces jerk and excitation of extraneous system resonances.

2 Block Diagram

A block diagram illustrates the internal components of the SR2 drive, including the DSP, shift register, gate drivers, MOSFETs, voltage detectors, and various regulators, all connected to the motor and input/output signals.

3 Specifications

3.1 Electrical Specification

3.2 Ambient Specification

4 Connecting

To use the SR2 drive models, the following are required:

• A power supply (12-48VDC)
• Pulse & Direction signal
• A compatible stepping motor

4.1 Connecting to Power Supply

If your power supply lacks a fuse or short-circuit current limiting device, install a fast-acting fuse (rated not to exceed 5 Amps) in series with the positive power supply lead. Connect the motor power supply "+" terminal to the drive terminal labeled "V+". Connect the power supply "-" to the drive terminal labeled "V-". Be careful not to reverse the wires.

4.2 Connecting to Motor

The manual provides diagrams illustrating how to connect different types of bipolar stepping motors (4-lead, 6-lead series, 6-lead center tap, 8-lead parallel, 8-lead series) to the SR2 drive.

4.3 Connecting to Inputs

4.3.1 Pulse & Direction Inputs

The SR Drive features two high-speed optically isolated inputs for STEP and DIR signals. They accept 5 to 24 Volt single-ended or differential signals, with frequencies up to 2MHz. The maximum input voltage is 28V. The motor advances one step with the falling edge of the STEP signal. The DIR signal determines the direction of rotation: a low signal (0 level) results in clockwise rotation, and a high signal (1 level) results in counterclockwise rotation.

4.3.2 EN Input

The EN input enables or disables the drive amplifier. It is an optically isolated input accepting 5 to 24 Volt single-ended or differential signals, with a maximum input voltage of 28V. When the EN input is closed, the driver amplifier is deactivated, and all MOSFETs shut down, leaving the motor free. When the EN input is open, the drive is activated. If the drive is in an error state and the fault is removed, a falling signal on the EN input will reset the error status and reactivate the driver amplifier.

4.3.3 Connecting Circuit

The document includes diagrams showing connection circuits for sinking outputs, sourcing outputs, and differential outputs, illustrating how to connect the control signals (STEP, DIR, EN) to the SR Drives.

4.3.4 Error Code

The SR Drive has two LEDs (red/green) to indicate status. A solid green LED signifies normal status. If the red LED flashes, an error has occurred. Errors are indicated by combinations of red and green flashes:

• Solid green: Motor disabled
• Flashing green: Motor enable
• 3 red, 1 green: Over Temperature
• 3 red, 2 green: Internal Voltage Bad
• 4 red, 1 green: Over Voltage
• 4 red, 2 green: Under Voltage
• 5 red, 1 green: Over current/Short circuit
• 6 red, 1 green: Open motor winding

5 Switch Selecting

The SR2 drive's functionality can be configured using DIP switches SW1 through SW12.

5.1 Running Current

The output current is set using switches SW1, SW2, and SW3, offering 8 different settings. The current value can be adjusted to meet customer requirements.

5.2 Idle Current

The drive features an automatic idle current reduction function that lowers the motor running current by 50% when the motor is not moving. This feature can be disabled if 90% running current is required when the motor is stationary, which is useful for applications needing high holding torque. To minimize motor and drive heating, enabling the idle current reduction is recommended unless the application strictly prohibits it.

5.3 Microstepping

The microstep resolution is set using switches SW5, SW6, SW7, and SW8, providing 16 different settings.

5.4 Self Test

Setting SW9 to "ON" after the drive is powered up will cause the drive to perform a "Self Test" of 2 revolutions, moving both CW and CCW at 1rps.

5.5 Command Signal Smoothing

SW10 selects the function: "ON" = Enable, "OFF" = Disable. Command signal smoothing can soften the effect of immediate changes in velocity and direction, making the motor's motion less jerky. An added advantage is that it can reduce wear on mechanical components. This function may introduce a slight delay in following the control signal; select it based on your application.

5.6 Load Inertia

SW11 selects the load inertia: "ON" = High inertia, "OFF" = Low inertia. Different inertia selections help the SR2 drive calculate the current control parameter, which is used in Anti-Resonance. If the load inertia is similar to the motor rotor, select low. If the load inertia is higher than the rotor, select high.

5.7 Digital Signal Filter

SW12 selects the digital signal filter: "ON" = 150 KHz, "OFF" = 2 MHz. The STEP and DIR signal inputs have a built-in digital filter to reduce external noise. If the system operates at low microsteps, select 150 KHz. If the system operates at high microsteps, select 2 MHz.

6 Motor Select

The SR2 can drive all types of two-phase step motors. MOONS' recommends several typical motors for the SR2 that cover most applications and offer better performance.

6.1 Recommended Motors

The manual details specifications and provides dimensional drawings for the following motor series:

11HS Series 1.8°

Includes parameters such as Part#, Connection, Length, Motor Holding Torque, # of Leads, Step Angle, Amps, Ohms, Motor Inertia, and Motor Weight.

11HY Series 1.8°

Includes parameters such as Part#, Connection, Length, Motor Holding Torque, # of Leads, Step Angle, Amps, Ohms, Motor Inertia, and Motor Weight.

17HD Series 1.8°

Includes parameters such as Part#, Connection, Length, Motor Holding Torque, # of Leads, Step Angle, Amps, Ohms, Motor Inertia, and Motor Weight.

6.2 Torque Curves

Torque curves are provided for various motor models (11HS5008-01, 14HYB401-03, 17HD2401-03N, 17HD4435-02N, 17HD6404-05N) showing the relationship between torque and speed at different voltage settings (24V and 48V) and microstep resolutions.

7 Drive Mounting

7.1 Mechanical Outline

A mechanical outline drawing provides the dimensions of the SR2 drive in millimeters.

7.2 Mounting the Drive

The drive can be mounted on the wide or narrow side of a chassis. Use M3 screws through the four corner holes for wide-side mounting and in the two side holes for narrow-side mounting. The amplifiers generate heat; ensure compulsory air-cooling for continuous operation at maximum power. Avoid mounting in spaces with no airflow or where ambient temperature exceeds 40°C. Do not expose the drive to moisture or metal particles.

8 Contacting MOONS'

Contact information for MOONS' Headquarters and various branch offices (Shenzhen, Beijing, Nanjing, Qingdao) and the Europe Branch (Moons' Industries (Europe) S.R.L.) is provided, including addresses, telephone numbers, and fax numbers.