Five test points to understand the efficiency and performance of the motor drive
A motor driver is a commonly used technology that converts the constant voltage of an independent AC power source into a variable voltage for controlling the torque and speed of the motor, making it ideal for use in motors that drive mechanical equipment loads. Motor drives offer higher efficiency than simple in-line motors and have less control than simple direct drive motors. These factors can save energy costs, improve production performance and extend motor life.
According to the US Department of Energy (DOE), motor systems are critical to the operation of almost all plants, accounting for 60% to 70% of total electricity use. DOE also identified variable frequency drives (VFDs) as a source of significant cost savings for the plant. Not surprisingly, motor drives are commonly used in many industries and facilities. To ensure the uptime of these motor systems, performing maintenance and troubleshooting has become a top priority.
Testing the challenges of motor drives
Troubleshooting and testing of motor drives (also known as variable frequency drives (VFDs), variable speed drives (VSD), or adjustable speed drives (ASD)) is typically performed by experts using a variety of test instruments, including oscilloscopes, multimeters, or other tools. carried out. These tests may involve a certain degree of trial and error using the old exclusion method. Due to the complexity of the motor system, testing is usually done once a year unless the system begins to fail. Considering that equipment often lacks a work history or work history is incomplete, determining where to start testing can be problematic. This includes recording specific tests and measurements that were previously performed, completed work, or adjusted conditions for individual components. Advances in test technology have eliminated some of the challenges. Newer instruments such as the FlukeMotorDriveAnalyzer (MDA-510 and MDA-550) are designed to make motor drive testing more efficient and insightful, and to document the entire process step by step. These reports can be saved and compared to subsequent test results for a more complete understanding of the motor drive maintenance history.
Simpler VFD troubleshooting method
These advanced motor driver analyzers combine the capabilities of instruments, handheld oscilloscopes, and recorders with the guidance of a skilled instructor, using screen tips, clear setup drawings, and step-by-step instructions written by motor driver experts to guide you through the basic tests. This new approach to decomposing and simplifying complex testing enables experienced motor drive specialists to work quickly and confidently to get the detailed information they need. It also opens the door for less experienced technicians to start motor drive analysis faster.
By implementing a standard set of tests and measurements at key points within the system, you can find the root cause of a motor drive system failure or perform a routine preventive maintenance check. Starting from the power input, the key tests are completed using different measurement techniques and evaluation criteria throughout the system, and finally at the output.
The following are basic tests for troubleshooting a motor drive:
Please note that FlukeMotorDriveAnalyzer will guide you through these tests and automate many of the calculations you need to give you confidence in your results. In addition, you can save data to reports at almost any test point, so you can upload documents to a computerized maintenance management system (CMMS) or share them with colleagues or consultants.
Safety Tips: Be sure to read the product safety instructions before starting the test. Do not work alone, please comply with local and national safety regulations. Wear personal protective equipment (approved rubber gloves, protective masks, and flame retardant clothing, etc.) to protect yourself from electric shock and arcing when exposed to live conductors.