In recent decades, inverters have emerged as one of the most essential technologies in industry and other advanced technology fields. These devices play a crucial role in converting electrical energy and providing flexibility in its usage. However, like any other technology, inverters may encounter problems and issues that can affect their performance and efficiency. Therefore, recognizing and resolving these issues is vital to ensuring the continued proper functioning of these devices.
This article focuses on introducing and examining methods for addressing common issues in inverters. Initially, the main causes of various problems in inverters are examined to identify the best possible solutions for their resolution. These causes include technical, environmental, and performance factors that can directly impact and lead to problems.
Given the importance of this topic and the direct connection of inverters with various industries, this article emphasizes that addressing common issues in inverters not only improves the performance and efficiency of these devices but also plays a significant role in reducing maintenance and repair costs. Therefore, a deeper understanding in this area and the proper implementation of troubleshooting methods are essential and vital for any organization or company utilizing this technology.
Fault Diagnosis
Diagnosing Simple Errors:
Checking Environmental Alerts and Warnings:
Environmental alerts and notifications from equipment may indicate simple errors. Temperature, pressure, or normal operation alerts can indicate simple errors.
Reviewing Logs and Registers:
Reviewing equipment logs and registers can indicate any sudden changes or errors in the system. These may provide valuable information about the cause of the problem.
Simple Measurement Tests:
Simple tests such as voltage, current, and temperature measurements can help identify simple problems such as breaks or short circuits.
Inspecting Physical Connections:
Inspecting physical connections can identify simple issues such as loose connections or damaged cables.
Diagnosing Serious Errors:
Reading Error Codes:
Some inverters provide error codes that can help identify the exact problem. Check the user manual or technical guide. Below are some common error codes introduced.
Ground Fault Error (GFT):
Cause: Excessive ground connection.
Resolution: Check wires and electrical connections.
Check for faults in motor insulation.
Correct ground connections.
Overcurrent Error (OCT):
Cause: Increase in output current.
Resolution: Properly adjust ACC and DEC settings.
Select an appropriate drive for the load current.
Check output connections for short circuits.
Overload Error (IOT or OLT):
Cause: Output current exceeds limit.
Resolution: Review and optimize drive settings.
Increase drive power or load capacity.
Overheat Error (OHT):
Cause: Excessive heat in the drive.
Resolution: Increase drive cooling system.
Reduce ambient temperature.
Output Phase Loss Error (POT):
Cause: One of the output phases is disconnected.
Resolution: Check physical connections to the motor.
Inspect motor screws and contactors.
Overvoltage Error (OVT):
Cause: High-line voltage increase.
Resolution: Properly adjust DEC.
Use mechanical brake unit.
Check mains voltage.
Undervoltage Error (LVT):
Cause: Decrease in DC link voltage.
Resolution: Adjust input voltage to the appropriate level.
Replace contactor in drive input.
Using Diagnostic Tools:
Using diagnostic tools such as multimeters, oscilloscopes, or mapping tools can help analyze signals and identify electrical problems.
Voltage and Current Inspection:
Measuring voltages and currents at various points of the system can reveal weaknesses and faults.
Consultation with Specialized Technicians:
If you cannot identify the fault, consulting and collaborating with a technician or engineer specialized in inverters can assist you in resolving the problem.
Types of Faults and Issues
Power Activation Switch Malfunction:
Error: The battery power switch is not functioning or does not activate.
Solution: First, ensure that the power switch is correctly connected and the battery is intact. If the problem persists, check the connections, and if necessary, replace the power switch or battery.
Battery Terminal Damage:
Error: Damage to battery terminals.
Solution: First, ensure that the battery connections are properly made, and the terminals are clean and free of corrosion. If there is corrosion, clean it and recheck the connections.
Excessive Current:
Error: The output current of the inverter exceeds the permissible limit.
Solution: Review the ACC and DEC settings and adjust them to appropriate values. If needed, check the output connections and address issues like short circuits.
Ground Fault:
Error: Battery or system grounds have become disconnected.
Solution: Check the ground connections and replace them if necessary. Ensure that the connections are properly made, and there are no disconnections.
Capacitor Issues:
Error: Possible problems with capacitors, including weakening or failure.
Solution: Thoroughly inspect the capacitors in the inverter and replace any weak or failed capacitors with new ones of suitable quality. When installing new capacitors, ensure that they are not damaged in any way.
Drive Malfunction:
Error: Malfunctions in the performance or efficiency of the inverter drive.
Solution: Check the drive settings and revert them to the correct operational settings. If the problem persists, examine the drive with diagnostic tools and address any technical issues.
High Voltage Drop:
Error: Reduction in output voltage power due to heavy load.
Solution: Reduce the load or, if possible, increase the drive capacity. Additionally, check the input voltage system and adjust voltage settings if necessary.
Interface Board Failure:
Error: Malfunction in the interface board’s performance, leading to loss of communication with other system components.
Solution: Inspect the connections of the interface board and replace it if needed. Also, ensure that there are no hardware failures on the board.
Controller Communication Failure:
Error: The inverter controller fails to establish communication.
Solution: Check the controller connections and adjust them if necessary, or replace the controller.
Motor Overload:
Error: Motor energy consumption exceeds the permissible limit.
Solution: Reduce the motor load, or if necessary, replace the motor with a higher-capacity model. Also, review motor control settings and adjust them to permissible values.
Excessive Heat:
Error: The inverter unit’s temperature exceeds the permissible limit.
Solution: Inspect the unit’s cooling system and ensure proper airflow. If the problem persists, use another cooling unit or repair/replace it.
Diode Bridge Damage:
Error: Damage to the diode bridge and protective equipment such as varistors, etc.
Solution: Initially, ensure that the type and input voltage of the inverter match the grid voltage or power source. In case of abnormal voltage changes, use voltage regulators. To address the issue, inspect and replace the diode bridges and protective equipment if necessary. Also, to prevent further damage, it’s recommended to use fuses or protective relays.
General Steps for Inverter Repair
Diagnosing the Problem:
In this stage, using various measuring tools such as a multimeter and an oscilloscope, the main issue with the inverter is identified. Troubleshooting starts from simpler stages, such as checking input and output voltages and currents, then progresses to more complex stages involving the examination of electronic circuits and main components. The initial stage commonly begins with visual inspections on circuits or analyzing various voltages and currents.
Inspecting Electronic Components:
In this stage, electronic components of the inverter such as transistors, diodes, capacitors, and resistors are examined using tools like a multimeter and an oscilloscope. This examination includes measuring resistances, testing diodes and transistors, and inspecting various electrical connections and combinations. The aim of this stage is to identify the faulty or damaged component for repair or replacement.
Replacing Faulty Components:
After identifying the faulty component, it needs to be replaced. For this purpose, replacement parts with similar specifications or improved specifications should be used. Component replacement may include transistors, diodes, capacitors, and resistors. After replacement, ensure that the new components are properly installed and electrically connected.
Inspecting Wires and Connections:
This stage involves inspecting various wires, connectors, and electrical connections. This includes checking for any wire corrosion, breakage, or improper connections. If any issues are found, repair or replace them to ensure proper electrical connections.
Repairing Electronic Circuits:
If necessary, electronic circuits inside the inverter undergo repair. This includes repairing power and control circuits that may be affected due to failures of faulty components. This stage requires technical knowledge and expertise in electronics.
Checking Voltages and Currents:
In this stage, input and output voltages and currents of the inverter are checked. This involves measuring voltages and currents using appropriate measuring tools. The goal of this check is to ensure the accuracy of voltage and current operations during the inverter’s performance.
Performance Testing:
After repairs, the performance of the inverter must be tested to ensure the problem has been resolved and its operation is accurate. This includes checking whether the inverter operates properly, stably, and under various conditions or not.
Settings and Configuration:
If necessary, the settings and configuration related to the inverter’s performance must be adjusted again. This includes settings related to output voltage, frequency, and other inverter parameters.
Final Testing:
After repairs and adjustments, the inverter should be tested again to ensure its final performance accuracy. This stage involves a comprehensive test of the overall performance of the inverter.
In conclusion, addressing common issues in inverters is vital for maintaining optimal performance of these devices. This process requires precision and technical expertise from electronic specialists to identify and diagnose problems accurately and take appropriate repair actions. Given that errors can have serious consequences for both inverters and connected equipment, the importance of this process has increased significantly.
Resolving common issues in inverters, such as identifying and repairing overcurrent faults, ground fault errors, overload faults, and excess heat faults, plays a crucial role in increasing the useful life and efficiency of these devices. By replacing or repairing faulty components, thoroughly checking connections and wiring, and adjusting software and hardware settings correctly, the inverter can be restored to optimal condition.
The importance of safety and optimal use of inverters in various industries should also not be overlooked. Proper actions in troubleshooting, as a key point, will lead to increased productivity, cost reduction, and maintaining the stability of electrical systems. These measures also play a crucial role in preventing serious damage to equipment and facilities connected to inverters. In other words, effective approaches to addressing inverter issues are of paramount importance in the field of technology and industry.