Mericwell Inverter MK300 Instruction Manual Usage Guide

Introduction

The Mericwell MK300 series inverter, as a high-performance vector inverter, is widely applied in various industrial automation scenarios. With its rich functions, stable performance, and flexible control methods, it has gained widespread recognition in the market. This article, based on the official manual of the MK300 inverter, provides a detailed introduction to its operation panel functions, password setting and removal, parameter access restrictions, factory reset, external terminal control, frequency regulation via potentiometer, and solutions to common fault codes, helping users better understand and use this inverter.

I. Operation Panel Function Introduction

1.1 Overview of the Operation Panel

The operation panel of the MK300 inverter integrates multiple function keys and display interfaces, facilitating users in parameter setting, status monitoring, and operation control. The operation panel mainly consists of a multi-function selection key (M.F key), an LED display, function keys (such as the STOP/RESET key), and digital/function selection keys.

1.2 Introduction to Main Function Keys

• M.F Key: The multi-function selection key is used to switch between different function menus, such as function parameter groups and user-customized parameter groups.
• STOP/RESET Key: The stop/reset key is used to stop the inverter operation or reset fault conditions.
• LED Display: It displays the inverter’s running status, parameter values, and fault information, etc.
• Digital/Function Selection Keys: These keys are used to input numerical values, select functions, or modify parameters.

1.3 Password Setting and Removal

The MK300 inverter offers a password protection function to prevent unauthorized parameter modifications.

Password Setting Steps:

1. Enter the parameter setting mode: Access the parameter setting menu through the operation panel.
2. Select the password parameter: Locate parameter PP-00 (User Password Setting) and input the desired password value.
3. Save the setting: Confirm the password is correct, then save and exit.

Password Removal Steps:

1. Enter the parameter setting mode: Access the parameter setting menu through the operation panel.
2. Clear the password parameter: Set the PP-00 parameter value to 0 to remove password protection.
3. Save the setting: Confirm the change and save.

1.4 Parameter Access Restrictions

The MK300 inverter allows users to set parameter access restrictions to prevent non-authorized personnel from modifying critical parameters.

Setting Steps:

1. Enter the parameter setting mode: Access the parameter setting menu through the operation panel.
2. Select the access restriction parameter: Locate parameter PP-03 (Personalized Parameter Group Display Selection) and set the parameter groups that can be displayed and modified according to needs.
3. Set password protection: For a higher level of protection, combine it with the password setting function to ensure that only users who know the password can modify restricted parameters.

1.5 Factory Reset

When it is necessary to restore all parameters of the inverter to their factory default values, the factory reset function can be used.

Operation Steps:

1. Enter the parameter setting mode: Access the parameter setting menu through the operation panel.
2. Select the factory reset parameter: Locate parameter PP-01 (Parameter Initialization) and set it to 1 (restore factory parameters, excluding motor parameters) or 3 (restore factory parameters, including motor parameters).
3. Confirm and execute: Confirm the operation as prompted, and the inverter will automatically restore to factory settings and restart.

II. External Terminal Control and Frequency Regulation via Potentiometer

2.1 External Terminal Forward/Reverse Rotation Control

The MK300 inverter supports forward/reverse rotation control of the motor through external terminals, offering flexible and convenient practical applications.

Wiring Steps:

1. Confirm terminal definitions: Refer to the inverter manual to confirm the terminals used for forward/reverse rotation control (e.g., X1, X2).
2. Connect control signals: Connect external control signals (such as switch signals) to the corresponding terminals, e.g., X1 for forward rotation signals and X2 for reverse rotation signals.
3. Common ground connection: Ensure that the control signal source and the inverter share a common ground to ensure stable signal transmission.

Parameter Setting Steps:

1. Enter the parameter setting mode: Access the parameter setting menu through the operation panel.
2. Set terminal functions: Locate parameters P4-00 (X1 Terminal Function Selection) and P4-01 (X2 Terminal Function Selection) and set them to forward rotation operation and reverse rotation operation, respectively.
3. Save the setting: Confirm the parameters are correct, then save and exit.

2.2 External Potentiometer Frequency Regulation

The MK300 inverter supports frequency setting through an external potentiometer to achieve motor speed control.

Wiring Steps:

1. Confirm analog input terminals: Refer to the inverter manual to confirm the terminals used for analog input (e.g., AI1, AI2).
2. Connect the potentiometer: Connect the two ends of the external potentiometer to the AI1 (or AI2) and GND terminals, respectively, with the middle tap serving as the frequency setting signal.
3. Common ground connection: Ensure that the potentiometer and the inverter share a common ground to ensure stable signal transmission.

Parameter Setting Steps:

1. Enter the parameter setting mode: Access the parameter setting menu through the operation panel.
2. Set the frequency setting source: Locate parameter P0-03 (Main Frequency Source X Selection) and set it to AI1 (or AI2, depending on the actual wiring).
3. Adjust the input range: According to needs, adjust the input range of AI1 (or AI2) through parameters P4-13 to P4-16 to match the output range of the potentiometer.
4. Save the setting: Confirm the parameters are correct, then save and exit.

III. Common Fault Codes and Solutions

3.1 Overview of Fault Codes

During the operation of the MK300 inverter, if an abnormal situation is detected, it will display the corresponding fault code through the operation panel and take protective measures. Users need to troubleshoot the cause according to the fault code and take corresponding solutions.

3.2 Common Fault Codes and Solutions

Acceleration Overcurrent (Err02)

Fault Causes:

• The output circuit of the inverter is grounded or short-circuited.
• The control mode is vector and parameter identification has not been performed.
• The acceleration time is too short.
• The manual torque boost or V/F curve is inappropriate.
• The voltage is too low.
• Starting a rotating motor.
• Sudden load addition during acceleration.
• The inverter is undersized.

Solutions:

• Check and eliminate output circuit grounding or short-circuit faults.
• Perform motor parameter identification.
• Increase the acceleration time.
• Adjust the manual torque boost or V/F curve.
• Adjust the voltage to the normal range.
• Select speed tracking start or wait for the motor to stop before starting.
• Cancel sudden load addition.
• Select an inverter with a higher power rating.

Module Overheating (Err14)

Fault Causes:

• High ambient temperature.
• Blocked air duct.
• Damaged fan.
• Damaged module thermistor.
• Damaged inverter module.

Solutions:

• Lower the ambient temperature.
• Clean the air duct.
• Replace the fan.
• Replace the thermistor.
• Replace the inverter module.

External Device Fault (Err15)

Fault Causes:

• An external fault signal is input through the multi-function terminal X.
• An external fault signal is input through the virtual IO function.

Solutions:

• Check and reset the external fault signal.
• Check the virtual IO function settings to ensure they are correct.

Communication Fault (Err16)

Fault Causes:

• The upper computer is not working properly.
• The communication line is abnormal.
• The communication parameter PD group settings are incorrect.

Solutions:

• Check the upper computer wiring and working status.
• Check if the communication connection line is normal.
• Correctly set the communication parameter PD group.

Motor Tuning Fault (Err19)

Fault Causes:

• The motor parameters are not set according to the nameplate.
• The parameter identification process times out.

Solutions:

• Correctly set the motor parameters according to the motor nameplate.
• Check if the leads from the inverter to the motor are in good condition.

Conclusion

This article has provided a detailed introduction to the operation panel functions, password setting and removal, parameter access restrictions, factory reset, external terminal control, frequency regulation via potentiometer, and solutions to common fault codes of the Mericwell MK300 inverter. Through this introduction, users can better understand and use the MK300 inverter, improving equipment operation efficiency and stability. In practical applications, users should reasonably configure the inverter parameters and functions according to specific needs and scenarios to achieve the best control effect.

Table of Contents

1. Introduction
   • The Role of Inverters in Industrial Automation
   • Overview of Hyundai N700E Inverters
   • Importance of Overcurrent Faults
2. Understanding Overcurrent Faults (E30.4)
   • What Is an Overcurrent Fault?
   • Meaning of the E30.4 Fault Code
   • Overcurrent Protection Mechanisms
3. Common Causes of E30.4 Faults
   • Overloaded Conditions
   • Incorrect Parameter Settings
   • Power Supply Issues
   • Mechanical Failures
   • Internal Inverter Faults
4. Diagnostic Steps for E30.4 Faults
   • Using the Digital Operator to View Fault Information
   • Inspecting the Motor and Load
   • Checking Power Supply and Wiring
   • Reviewing Inverter Parameters
   • Inspecting Inverter Hardware
5. Solutions for E30.4 Faults
   • Adjusting Acceleration Time
   • Optimizing Motor Parameters
   • Addressing Power Supply Issues
   • Fixing Mechanical Failures
   • Repairing or Replacing Inverter Hardware
6. Preventive Measures for E30.4 Faults
   • Regular Maintenance and Inspections
   • Correct Parameter Configuration
   • Using High-Quality Power Supplies and Wiring
   • Monitoring Load and Environmental Conditions
7. Advanced Diagnostics and Tools
   • Using Oscilloscopes and Multimeters
   • Leveraging Communication Features of N700E Inverters
   • Analyzing Fault Logs
8. Case Studies
   • Case Study 1: Overloaded Condition Causing E30.4 Fault
   • Case Study 2: Incorrect Parameter Settings Causing E30.4 Fault
   • Case Study 3: Unstable Power Supply Causing E30.4 Fault
9. Conclusion and Recommendations
   • Summary of E30.4 Fault Diagnosis and Solutions
   • Best Practices
   • Resources for Further Learning

1. Introduction

1.1 The Role of Inverters in Industrial Automation

Inverters, also known as Variable Frequency Drives (VFDs), are essential components in modern industrial automation systems. They regulate the speed of electric motors by adjusting the frequency and voltage of the power supplied to the motor. This capability enhances energy efficiency, reduces operational costs, and extends the lifespan of equipment. Inverters are widely used in applications such as fans, pumps, conveyors, and machine tools, where precise control of motor speed is critical.

1.2 Overview of Hyundai N700E Inverters

The Hyundai N700E series inverters are high-performance devices designed for industrial applications. Key features include:

• Energy Efficiency: Advanced control algorithms optimize motor performance.
• Versatility: Supports multiple control modes, including V/F control and sensorless vector control.
• Reliability: Built-in protection features such as overcurrent, overload, overvoltage, and undervoltage protection.
• User-Friendly Interface: Equipped with a digital operator for easy parameter configuration and fault diagnosis.

The N700E series is widely used in industrial settings, including fans, pumps, compressors, and other machinery.

1.3 Importance of Overcurrent Faults

Overcurrent faults are among the most common issues encountered in inverter operations. If not addressed promptly, they can lead to equipment damage, production downtime, and safety hazards. Understanding the causes, diagnostic methods, and solutions for overcurrent faults is crucial for maintenance personnel and engineers.

2. Understanding Overcurrent Faults (E30.4)

2.1 What Is an Overcurrent Fault?

An overcurrent fault occurs when the output current of an inverter exceeds its rated value or the set protection limit. This triggers the inverter’s protection mechanism, causing it to shut down to prevent damage. Overcurrent faults can be caused by various factors, including excessive loads, incorrect parameter settings, and power supply issues.

2.2 Meaning of the E30.4 Fault Code

In Hyundai N700E inverters, the E30.4 fault code indicates an overcurrent condition. When this code appears, it means the inverter has detected an output current exceeding the preset protection limit. Immediate action is required to diagnose and resolve the issue.

2.3 Overcurrent Protection Mechanisms

Hyundai N700E inverters are equipped with multiple protection mechanisms to prevent damage from overcurrent conditions:

• Hardware Protection: Current sensors monitor the output current in real-time. If the current exceeds the limit, the inverter cuts off the output.
• Software Protection: Parameters can be adjusted to set the sensitivity and response time of the overcurrent protection.

3. Common Causes of E30.4 Faults

3.1 Overloaded Conditions

• Mechanical Jamming: The motor or mechanical load may be jammed, causing a sudden increase in current.
• Excessive Load: The motor may be operating under an excessive load for an extended period, leading to current levels beyond the inverter’s rating.

3.2 Incorrect Parameter Settings

• Short Acceleration Time: The acceleration time (A02) may be set too short, resulting in high starting currents.
• Incorrect Motor Parameters: The inverter’s motor parameters, such as rated current, power, and pole count, may not match the actual motor specifications.

3.3 Power Supply Issues

• Voltage Instability: The input voltage may fluctuate excessively or be too low.
• Phase Loss or Imbalance: A missing phase or voltage imbalance in the three-phase power supply can cause abnormal current levels.

3.4 Mechanical Failures

• Bearing Damage: Worn or damaged motor bearings can increase friction, leading to higher current draw.
• Transmission System Failures: Issues with belts, gears, or other transmission components can cause mechanical stress and increased current.

3.5 Internal Inverter Faults

• Aging Power Modules: The power modules or capacitors may degrade over time, leading to failures.
• Poor Cooling: Inadequate cooling due to fan failure or dust accumulation can cause overheating and trigger overcurrent protection.

4. Diagnostic Steps for E30.4 Faults

4.1 Using the Digital Operator to View Fault Information

• Access the d13 (Trip event monitor) mode on the digital operator to view the current, frequency, and other data at the time of the fault.
• Check d14-d16 (Trip history) to review past fault records.

4.2 Inspecting the Motor and Load

• Verify that the motor and mechanical load are operating normally, without jamming or abnormal resistance.
• Inspect transmission components (belts, gears, bearings) for damage or obstructions.

4.3 Checking Power Supply and Wiring

• Use a multimeter to measure the input voltage (R, S, T) and ensure it is balanced and within the acceptable range.
• Check for loose or poorly connected wiring terminals.

4.4 Reviewing Inverter Parameters

• Confirm that parameters such as acceleration time (A02) and motor rated current (A06) are correctly set.
• Review overload protection levels (b07) to ensure they are appropriately configured.

4.5 Inspecting Inverter Hardware

• Ensure the cooling fan is operating correctly and the heat sink is free of dust and debris.
• Inspect power modules and capacitors for signs of damage, such as burning, bulging, or leakage.

5. Solutions for E30.4 Faults

5.1 Adjusting Acceleration Time

• Increase the acceleration time (F02) to reduce the starting current.

5.2 Optimizing Motor Parameters

• Ensure the inverter’s motor parameters (rated current, power, pole count) match the actual motor specifications.

5.3 Addressing Power Supply Issues

• Stabilize the input voltage and ensure it is balanced across all three phases.
• Use voltage regulators or filters to improve power quality.

5.4 Fixing Mechanical Failures

• Repair or replace damaged bearings, belts, gears, or other mechanical components.

5.5 Repairing or Replacing Inverter Hardware

• Replace faulty power modules or capacitors.
• Clean the heat sink to ensure proper cooling.

6. Preventive Measures for E30.4 Faults

6.1 Regular Maintenance and Inspections

• Conduct regular inspections of motors and mechanical loads.
• Clean the inverter’s heat sink and cooling fan periodically.

6.2 Correct Parameter Configuration

• Configure inverter parameters accurately based on the motor and load specifications.

6.3 Using High-Quality Power Supplies and Wiring

• Ensure a stable power supply and secure wiring connections.

6.4 Monitoring Load and Environmental Conditions

• Avoid prolonged operation under overloaded conditions.
• Ensure the inverter operates in a suitable environment (temperature, humidity, dust-free).

7. Advanced Diagnostics and Tools

7.1 Using Oscilloscopes and Multimeters

• Use an oscilloscope to monitor current and voltage waveforms for diagnosing power supply and load issues.
• Use a multimeter to measure voltage, current, and resistance.

7.2 Leveraging Communication Features of N700E Inverters

• Utilize the RS485 communication interface to transmit inverter data to a computer for remote monitoring and diagnostics.

7.3 Analyzing Fault Logs

• Analyze the inverter’s fault logs to identify patterns and root causes of faults.

8. Case Studies

8.1 Case Study 1: Overloaded Condition Causing E30.4 Fault

• Problem: A fan frequently experienced E30.4 faults during startup.
• Diagnosis: Inspection revealed a jammed fan impeller.
• Solution: Cleaning the impeller and lubricating the bearings resolved the issue.

8.2 Case Study 2: Incorrect Parameter Settings Causing E30.4 Fault

• Problem: A pump inverter displayed E30.4 faults during startup.
• Diagnosis: The acceleration time (A02) was set too short.
• Solution: Increasing the acceleration time eliminated the fault.

8.3 Case Study 3: Unstable Power Supply Causing E30.4 Fault

• Problem: A conveyor inverter experienced sudden E30.4 faults during operation.
• Diagnosis: The input voltage was found to be highly unstable.
• Solution: Installing a voltage regulator resolved the issue.

9. Conclusion and Recommendations

9.1 Summary of E30.4 Fault Diagnosis and Solutions

E30.4 faults are typically caused by overloaded conditions, incorrect parameter settings, or power supply issues. Systematic diagnostic steps can quickly identify the root cause and implement appropriate solutions.

9.2 Best Practices

• Perform regular maintenance and inspections of inverters and motors.
• Configure inverter parameters accurately.
• Use high-quality power supplies and wiring.
• Monitor load and environmental conditions.

9.3 Resources for Further Learning

• Hyundai N700E Inverter User Manual
• Training courses on inverter maintenance and fault diagnosis
• Professional technical forums and communities

Appendix: Common Fault Code Table

This article provides a comprehensive guide to diagnosing and resolving E30.4 overcurrent faults in Hyundai N700E inverters. It is designed for engineers and maintenance personnel to better understand and address this common issue.

Introduction

The Xintian NSD-A/P series frequency converter is a high-performance, low-voltage, multi-functional device suitable for industrial applications ranging from 0.4 kW to 560 kW. This series supports vector control and V/F control, and is equipped with advanced PLC function interfaces and various communication protocols, such as RS485/Modbus. It is an ideal choice for modern industrial equipment. This document provides a detailed introduction to the operation panel functions, parameter settings, external control, and troubleshooting methods to help users safely and efficiently utilize the equipment.

Part 1: Introduction to Operation Panel Functions

Basic Structure of the Operation Panel

• LED Display: Shows output frequency, current, voltage, or fault codes. For example, in running mode, it defaults to displaying the current frequency, such as “50.00” indicating 50 Hz.
• Status Indicators: Include DRV, FREF, FOUT, IOUT, FWD, REV, etc., used for quickly determining the status of the frequency converter.

Key Functions

• PRG (Program Key): Enters the parameter setting mode. Press and hold to return to the previous menu.
• ENTER (Confirm Key): Confirms selections or saves parameter modifications.
• UP/DOWN (Up/Down Keys): Increases or decreases parameter values and scrolls through menus.
• FWD/REV (Forward/Reverse Keys): Initiates forward or reverse operation.
• STOP/RESET (Stop/Reset Key): Stops operation or resets faults.

Parameter Initialization

1. Ensure the frequency converter is stopped, then press the PRG key to enter the parameter setting mode.
2. Navigate to F0.02 (Initialize Parameters), set it to 1, and press ENTER to confirm.
3. The frequency converter will flash “INIT” as a prompt. Initialization is complete when it automatically resets.

Password Setting and Removal

• Setting a Password: Enter F0.00, set a 4-digit password, and press ENTER to save.
• Removing a Password: Enter the correct password to unlock, then set F0.00 to 0 and press ENTER to save.

Parameter Access Restrictions

1. Enter F0.01 and set the access level (0 for full access, 1 for basic parameters, 2 for advanced parameters).
2. Press ENTER to save.

Part 2: External Terminal Forward/Reverse Control and External Potentiometer Speed Adjustment

External Terminal Forward/Reverse Control

• Wiring: Connect the FWD terminal to one end of a switch, and the other end of the switch to COM. Connect the REV terminal to one end of another switch, and the other end of that switch to COM.
• Parameter Settings:
  • Set F2.00 to 1 (External Terminal Control).
  • Set F2.01 to 1 (Two-Wire Control Mode 1).
• Power-On Test: Close the FWD switch for forward motor rotation, and close the REV switch for reverse motor rotation.

External Potentiometer Speed Adjustment

• Wiring: Connect one end of the potentiometer to +10V, the middle tap to AI1, and the other end to GND.
• Parameter Settings:
  • Set F0.01 to 2 (Analog AI1 Speed Adjustment).
  • Set F0.02 to 0.10s (Analog Input Filtering).
  • Set F0.03 and F0.04 to the minimum and maximum frequencies, respectively.
• Operation: Rotate the potentiometer while powered on to adjust the frequency.

Part 3: Frequency Converter Fault Codes and Solutions

Common Fault Codes and Solutions

General Fault Resolution Process

1. When a fault occurs, the panel displays the fault code, and the motor stops.
2. Press STOP/RESET to reset. If ineffective, power off for 5 minutes and try again.
3. Check the fault history and determine the cause based on the code.
4. Adjust parameters or inspect hardware, then test operation.

Conclusion

The Xintian NSD-A/P series frequency converter, with its powerful features and user-friendly design, is an excellent choice for industrial control. Through this guide, users can master the operation panel, parameter management, external control, and fault diagnosis. In practical applications, optimize parameters according to site conditions, such as using PID in pump systems to achieve constant pressure water supply, saving over 30% in energy. This manual emphasizes safety first; read all warnings before operating. For more advanced applications, such as Modbus communication or multi-speed settings, refer to the parameter table for expansion.

Introduction

In the realm of modern industrial automation, servo drives, as the core components of precision control systems, play a pivotal role. The VEICHI SD700 series servo drives are highly regarded for their high performance and reliability, finding widespread applications in fields such as CNC machine tools, robots, printing machinery, and packaging equipment. However, various faults may occur during the use of these products, among which the ER.C90 fault is relatively common, manifesting as encoder communication abnormalities. If not addressed promptly, such faults can not only disrupt production processes but also potentially lead to equipment damage or safety hazards.

Based on the detailed version of the VEICHI SD700 servo system manual and practical engineering experience, this article provides an in-depth analysis of the ER.C90 fault and offers a comprehensive and practical guide for diagnosis and troubleshooting. The aim is to assist engineers and technicians in quickly locating problems and enhancing system stability.

Overview of the SD700 Servo System

The VEICHI SD700 series servo drive is a high-performance AC servo system suitable for 200V and 400V voltage classes, supporting servo motors with power ranges from 100W to 7.5kW. This system employs advanced vector control technology, combined with high-resolution encoder feedback, to achieve closed-loop control, ensuring high precision and high dynamic response of the system.

Main Component Names and Functions of the System

• Servo Drive Main Body: Includes a display panel, CHARGE indicator light, and CN series interfaces (such as CN1 control terminals, CN2 encoder interface, and CN7 USB communication terminal). The display panel is used to display status codes, fault codes, and parameter settings.
• Servo Motor: Equipped with incremental or absolute encoders, supporting multi-turn absolute position feedback.
• Encoder: The core feedback component, typically with a resolution of 17 or 24 bits, used to provide motor position and speed information.
• System Block Diagram: The main circuit includes power input, regenerative resistor, and motor output; the control circuit involves PLC upper computers, I/O signals, and communication modules. The SD700 supports multiple communication protocols, such as RS485, CANopen, and EtherCAT, facilitating integration into industrial networks. An example of system composition includes an upper computer (such as a PLC), servo drive, motor, and load, forming a closed-loop control link.

Role of the Encoder in the Servo System

The encoder serves as a bridge connecting mechanical and electrical components, converting the physical motion of the motor into digital signals and providing real-time feedback to the drive. The SD700 servo system mainly uses optical incremental or absolute encoders with resolutions as high as 16,777,216 pulses per revolution (24 bits).

Working Principle of the Encoder

The encoder generates A, B, and Z phase signals (for incremental types) or multi-turn absolute position data (for absolute types) through optical or magnetic grating disks. These signals are transmitted to the drive via the CN2 interface, and the drive calculates the motor position, speed, and torque deviations accordingly to achieve PID closed-loop regulation. If communication is interrupted, the drive cannot obtain accurate feedback, leading to system out-of-control and triggering the ER.C90 fault.

Description of the ER.C90 Fault

The ER.C90 is a specific fault code for the VEICHI SD700 servo drive, displayed on the panel, such as a red LED showing “ER.C90”. This fault is classified as a “Class 1” alarm, meaning “encoder communication fault: disconnection.”

When the drive detects a loss or abnormality in the encoder signal, it immediately stops the motor output and triggers this alarm. Symptoms include:

• The motor fails to start or stops suddenly.
• The system reports an error and cannot enter the enabled state.
• The upper computer monitoring shows zero or abnormal values for position feedback.

Analysis of Fault Causes

The root cause of the ER.C90 fault lies in the interruption of the communication link between the encoder and the drive. The main reasons include:

• Signal wire disconnection or poor connection: Cable breakage due to bending, pulling, or aging during use. Loose or oxidized CN2 plugs can also cause poor contact.
• Incompatible cable specifications: Using non-original cables or improper shielding layers can lead to signal distortion.
• Excessive cable length: Exceeding the recommended length causes significant signal attenuation.
• External interference: Electromagnetic interference from devices such as frequency converters and welding machines. Improper shielding grounding exacerbates the problem.
• Motor or encoder damage: Failure of the internal photoelectric components of the encoder or wear of the motor bearings leading to unstable signals.
• Incorrect parameter settings: Mismatched motor group parameters or incorrect drive power ratings.
• Drive hardware failure: Damage to the communication module on the main board.

Diagnostic Steps

Diagnosing the ER.C90 fault requires a systematic approach, starting from simple to complex. Ensure that power is disconnected before operation to avoid the risk of electric shock.

• Preliminary Inspection: Observe the panel display to confirm it is an ER.C90 fault. Use the manual FN000 to view the alarm records.
• Cable Integrity Test: Use a multimeter to measure each signal wire of the CN2 interface to check for continuity and short circuits.
• Connection Inspection: Check the CN2 and motor-end plugs for dust, dirt, or oxidation. Re-plug and test.
• Cable Specification Verification: Measure the cable length and confirm that the model matches the requirements in the manual.
• Interference Investigation: Check the shielding layer grounding and keep away from interference sources. Try adding magnetic rings for filtering.
• Parameter Confirmation: Check parameters such as Pn000 (encoder type) and Pn100 (inertia ratio) for correctness.
• Hardware Testing: Replace with spare cables or motors for testing.
• Advanced Diagnosis: Connect the CN7 USB and use upper computer software to monitor Un003 (rotor position).

Solutions

Provide specific solutions for each cause:

• Disconnection/poor connection: Replace the cable or tighten the plugs.
• Incompatible specifications: Select the correct cable model and shorten the length.
• Excessive cable length: Optimize the layout to reduce the length.
• Interference: Improve grounding and add magnetic rings.
• Hardware damage: Replace the encoder or motor.
• Parameter errors: Reset the Pn parameters and restore factory settings before reconfiguration.
• Drive failure: Contact VEICHI after-sales service to replace the unit.

Preventive Measures

Prevention is better than cure. The following strategies can reduce the incidence of the ER.C90 fault:

• Regular maintenance: Check cables and connections every quarter and clean dust.
• Environmental optimization: Install in ventilated cabinets to avoid high temperatures. Use EMI filters.
• Cable management: Use fixed clips to secure cables and prevent pulling.
• Parameter backup: Use the upper computer to export parameters for easy restoration.
• Training: Train operators on correct installation to avoid misoperations.
• Redundancy design: In critical applications, use dual encoders or wireless feedback.

Case Studies

• Case 1: A printing factory using an SD700 servo drive for roller positioning suddenly encountered an ER.C90 fault, and the motor stopped. Diagnosis revealed a broken A-phase wire of the CN2 interface. Replacing the cable and adding a magnetic ring resolved the issue.
• Case 2: A factory had a welding machine nearby with poor grounding, causing interference. Adding shielding resolved the ER.C90 fault.

Advanced Debugging Techniques

For stubborn faults, use the upper debugging tools in Chapter 14 of the manual:

• Upper computer connection: Connect via the CN7 USB, install the driver, and open the software.
• Real-time monitoring: View Un140 bus voltage and Un003 position feedback.
• Digital oscilloscope: Capture the encoder signal waveform and analyze distortion.
• Auxiliary functions: Perform FN105 vibration initialization and use EASYFFT to eliminate mechanical interference.

Conclusion

Although the ER.C90 fault is common, it can be efficiently resolved through systematic diagnosis and guidance from the manual. The VEICHI SD700 servo system is renowned for its high reliability, and correct maintenance can ensure long-term stable operation. This article provides a comprehensive reference, hoping to be of assistance. For more details, refer to the official manual or contact support.

Abstract
The Leadshine L7 series AC servo drives are crucial components in the field of industrial automation. The startup display sequence reflects the device’s initialization status and operational readiness. This paper provides an in-depth analysis of the phenomenon where users observe a brief display of “1.d002” followed by a switch to “00ST,” indicating a normal initialization process. By interpreting the manual, safety precautions, and incorporating online resources from similar EL7 series, it explores the meanings of display codes, diagnostic methods, potential causes, and optimization strategies, aiming to offer comprehensive guidance to engineers and technicians.

Introduction
In modern industrial automation systems, servo drives play a pivotal role. The Leadshine L7 series AC servo drives utilize the latest DSP from Texas Instruments (TI), featuring high integration and reliability. Users often encounter startup display issues, such as the display showing “1.d002” briefly after power-on, followed by a switch to “00ST.” This paper centers on this phenomenon, conducting a systematic analysis by combining excerpts from the user manual and online resources, aiming to assist users in understanding the technical implications of the display sequence and providing practical diagnostic steps.

Servo Drive Fundamentals

Basic Principles

Servo drives drive servo motors to achieve precise motion by receiving command signals from an upper-level controller. The fundamental principles include triple-loop control (position loop, speed loop, and current loop), with PID algorithms at the core.

L7 Series Characteristics

The L7 series belongs to AC servo drives, supporting 220VAC input and a wide power range. The manual emphasizes that improper operation can lead to severe consequences, and users must adhere to safety precautions.

Key Components and Initialization

The key components of a servo system include the drive, motor, and encoder. The drive integrates a DSP processor, and the initialization process involves self-tests, parameter loading, and status monitoring.

Display Panel Basics

The display panel employs a seven-segment LED digital tube, supporting status display, parameter settings, and alarm prompts. Understanding these codes is crucial for diagnosing device status.

Control Modes and Parameter Settings

Servo drives offer control modes including position, speed, and torque modes. Parameter settings are achieved through panel buttons or MotionStudio software.

Safety Guidelines

The manual stresses that product storage and transportation must comply with environmental conditions, and user modifications will void the warranty.

Overview of the L7 Series

Product Features and Updates

The Leadshine L7 series is a fully digital AC servo drive, utilizing TI DSP, supporting stiffness tables, inertia identification, and vibration suppression. The version has evolved from V1.00 to V2.10 with continuous updates.

Application Areas and Manual Structure

The L7 series finds wide applications in PLC control, robotic arms, and other fields. The manual structure covers the preface, safety matters, specifications, installation, wiring, commissioning, and maintenance.

Wiring and Version Descriptions

Wiring includes power, motor, encoder, and I/O ports. The version description indicates program compatibility and content updates.

Display Panel in Detail

Operation Interface and Key Functions

The L7 drive’s operation interface consists of a 6-digit LED digital tube and 5 keys for status display and parameter settings.

Initialization and Monitoring Mode Codes

Upon power-on, the panel first displays initialization codes. “1.d002” may be a custom or transient display, and switching to “00ST” indicates a standby state. Monitoring mode codes include position deviation, motor speed, etc.

Alarm Code Interpretation

Alarm codes start with “Er,” and the absence of “Er” indicates normal operation.

Diagnostic Analysis

Core Phenomenon Interpretation

The display showing “1.d002” briefly followed by a switch to “00ST” is a normal sequence. The initialization process includes self-tests and parameter loading.

Potential Causes Explored

Potential causes include normal boot-up, configuration influences, and external factors.

Diagnostic Steps and Methods

Diagnostic steps include checking the display history, software verification, and factory reset.

Troubleshooting

Non-Normal Situation Exclusion Methods

If non-normal, exclusion methods include power supply checks, wiring verification, parameter resets, and software tuning.

Common Faults and Solutions

Common faults such as overcurrent and overload are unrelated to the display sequence.

Applications and Optimization

Case Studies: CNC Machine Tools and Robotic Arms

Case 1: A CNC machine tool uses the L7 to control axes, and a normal startup sequence ensures precision. Case 2: A robotic arm in bus mode uses EtherCAT synchronization to avoid delays.

Optimization Strategies and Future Trends

Optimization strategies include adjusting control modes and vibration suppression. Future trends involve integrating AI tuning.

Conclusion
The transition from “1.d002” to “00ST” indicates a normal state. Mastering diagnostic methods can enhance application efficiency. It is recommended to refer to the manual and technical support to ensure stable system operation.

The EST900 series inverter from Yiste, as a high-performance vector inverter, is widely applied in the control and speed regulation of three-phase asynchronous motors. This article, based on the official manual, will elaborate in detail on its operation panel functions, parameter setting methods, external terminal control and speed regulation implementation, as well as handling measures for common fault codes, helping users quickly master the usage skills.

I. Introduction to Operation Panel Functions and Parameter Settings

(A) Overview of Operation Panel Functions

The EST900 series inverter comes standard with an LED operation panel, which offers a variety of functions:

• Status Monitoring: It can display key information such as operating frequency, current, voltage, and fault codes in real time.
• Parameter Setting: It supports viewing and modifying functional parameters.
• Operation Control: Control commands such as start, stop, and forward/reverse rotation can be executed through the panel.
• Indicator Lights: It is equipped with indicator lights including RUN (operation), LOCAL/REMOT (control source), FWD/REV (direction), and TUNE/TC (tuning/torque/fault), which visually reflect the equipment status.

(B) Factory Parameter Settings

During debugging or when parameters are in disarray, a factory reset operation can be performed:

• Steps:
  • Enter the FP – 01 parameter.
  • Set it to 1 (restore factory parameters, excluding motor parameters).
  • Press the ENTER key to confirm.
  • Wait for the display to restore, indicating parameter initialization is complete.
• Notes:
  • FP – 01 = 2 can clear fault records and other information.
  • FP – 01 = 4 can back up the current parameters.
  • FP – 01 = 501 can restore the backed-up parameters.

(C) Password Setting and Clearing

To prevent misoperation, a user password can be set:

• Setting a Password:
  • Enter FP – 00 and set it to a non-zero value (e.g., 1234).
  • After exiting, the password needs to be entered when accessing parameters again.
• Clearing a Password:
  • Set FP – 00 to 0.

(D) Parameter Access Restrictions

Parameter access can be restricted in the following ways:

• Parameter Group Display Control:
  • Set the FP – 02 parameter to control whether Group A and Group U parameters are displayed.
  • For example, setting it to “11” can hide some parameter groups to prevent mismodification.
• Prohibition of Modification during Operation:
  • Some parameters marked with “★” cannot be modified during operation and need to be set after shutdown.

II. External Terminal Forward/Reverse Rotation Control and Potentiometer Speed Regulation

(A) External Terminal Forward/Reverse Rotation Control

• Wiring Terminals:
  • D11: Forward rotation (FWD)
  • D12: Reverse rotation (REV)
  • COM: Digital input common terminal
• Parameter Settings:
  | Parameter Code | Name | Setting Value | Description |
  | —- | —- | —- | —- |
  | F0 – 02 | Operation Command Selection | 1 | Terminal control |
  | F4 – 00 | D11 Function Selection | 1 | Forward rotation |
  | F4 – 01 | D12 Function Selection | 2 | Reverse rotation |
  | F4 – 11 | Terminal Command Mode | 0 | Two-wire type 1 |
• Note: If a three-wire control system is used, set F4 – 11 = 2 or 3 and cooperate with other DI terminals.

(B) External Potentiometer Speed Regulation

• Wiring Terminals:
  • +10V: Positive pole of potentiometer power supply
  • GND: Negative pole of potentiometer power supply
  • A11: Analog voltage input (0 – 10V)
• Parameter Settings:
  | Parameter Code | Name | Setting Value | Description |
  | —- | —- | —- | —- |
  | F0 – 03 | Main Frequency Command Selection | 2 | A11 |
  | F4 – 13~F4 – 16 | A11 Curve Settings | Adjust according to actual conditions | Minimum/maximum input corresponds to frequency |
• Tip: It is recommended that the potentiometer resistance be between 1kΩ and 5kΩ to ensure that the current does not exceed 10mA.

III. Common Fault Codes and Handling Methods

The EST900 series inverter has a comprehensive fault diagnosis function. The following are common faults and their handling methods:

(A) Overcurrent Faults

(B) Overvoltage Faults

(C) Other Common Faults

(D) Fault Reset Methods

• Press the STOP/RESET key on the panel.
• Set a DI terminal to the “Fault Reset” function (F4 – xx = 9).
• Write “2000H = 7” through communication.
• Power off and restart (wait for more than 10 minutes).

IV. Conclusion

The Yiste EST900 series inverter is powerful and flexible in operation, capable of adapting to various industrial scenarios. Through the introduction in this article, users can master the following key contents:

• Basic usage methods of the operation panel and parameter setting skills.
• How to control and regulate the speed of the motor using external terminals and a potentiometer.
• Diagnostic ideas and handling skills for common faults.
• Effective use of password management and parameter protection mechanisms.
  During actual use, it is recommended that users strictly follow the manual specifications for wiring and parameter setting, and regularly carry out maintenance work to ensure the long-term stable operation of the equipment.