Basics of Large Capacity Medium Voltage Motor and Adjustable speed Drive Factory Acceptance Test – How to be a witness?

On October 25th 2018, Manish Verma and Brandon Kim of TMEIC Corporation gave an educational seminar on the topic “Basics of large capacity Medium Voltage motor and adjustable speed drive factory acceptance test – How to be a witness?” to a group of 15 professionals at the HESS conference center. Houston. The session commenced with ASD-101 describing the basic building blocks of a medium voltage motor and drive system, and some of the ways they are being employed in the industry such as for soft starting, speed control, VAR compensation / PF improvement and energy savings. The talk then started by clearly defining what is a FAT, the purpose it solves, why is FAT an important application consideration in the early stages of procurement rather than after the fact, when should a FAT be selected and what are some of the common challenges associated with hosting an FAT.

Summary of the talk : Adjustable Speed Drives (ASD) commonly known as Variable Frequency Drives or just VFD have gained popularity on large Multi Megawatt motors driving critical services such as compressors, pumps, extruders and fans. Extensive literature exists on IEEE Xplore by virtue of conference proceedings on techno-commercial benefits, application and installation considerations in applying them. However, with the exception of testing large motors and drives individually little emphasis, if any, has been given on the factory acceptance stage (FAT) of a medium voltage (MV) ASD and motor procurement cycle. Parts of this seminar were presented at the 2016 IEEE PCIC conference held in Philedelphia, PA. A copy of the technical paper addressing this topic can be found at:

The first part of the session covered details on the various types of testing on an ASD. Manish Verma spoke about the prototype testing, functional witness test, runback reactor and back-to-back tests and how do they differ from each other. There is a common misconception among purchasers and specifiers that a standard witness test means that the VFD will be run at rated voltage and current using the project motor. This is not the case most of the times and usually the manufacturer will have a price adder to conduct additional tests or might not even have the capability in house for large multi-MW motors. IEEE 1566-2015 which is a performance standard for drives greater tha 375kW provides guidance on how what inspection and factory tests to conduct. An overview of how to fill out the data sheets and what other standards exists regarding testing were covered.

Brandon Kim addressed the motor part of the witness test. In comparision to MV drives, extensive literature and standards exist for motor testing, methods and acceptance criteria. However, it was refresing to see some of the key items that were covered during a “routine test,” “optional routine test,” and “complete test.” Since this session was held in the Energy capital of the world, special emphasis was given on the testing guidance provided by American Petroleum Institute (API) 541, 547 standard. They key highlight of Brandon’s presentation was an overview of how a witness test is performed, description of a typical inspection and test plan and things to look out for when attending a test.

The talk concluded by providing guidance on items that a personnel must do in preparation of attending an FAT, while at FAT and after a FAT is concluded. Seemingly trivial items such as asking “is there Wi-Fi available at the test facility,” are not confirmed beforehand leading to issues and hampering quick communications back to the project team which might be located in opposite time zones.

About TMEIC:

Toshiba Mitsubishi-Electric Industrial Systems Corporation (TMEIC) was formed in 2003 following the merger of the industrial systems departments of Toshiba Corporation and Mitsubishi Electric Corporation. TMEIC manufactures and sells variable frequency drives, motors, photovoltaic inverters and advanced automation systems for a range of industrial applications. TMEIC’s operation in North American is headquartered in Roanoke, VA that designs, develops and engineers advanced automation, large AC and DC motors, photovoltaic inverters and variable frequency drive systems. TMEIC Corporation specializes in the Renewable Energy, Metals, Material Handling, Oil & Gas, Mining, Testing and other industrial markets worldwide. We drive industry.

About the Speakers:

Brandon Kim is a Sales application engineer specializing in MV Motors at the TMEIC office in Houston, TX. Brandon received his BSc in Mechanical Engineering at the University of Warwick (UK) in 2006. He has since worked in the energy industry including several years at Hyundai Heavy Industries as an Application Engineer. His responsibilities include power systems, MV induction and synchronous machines, and technical training. He is an active member of API committee and IEEE.

Manish Verma is a senior sales application engineer with TMEIC. He graduated in 2006 from Virginia Tech with BSEE and began his career with TMEIC in 2006 while continuing his professional education. In 2009 he completed his MSEE with a concentration in power. After a broad exposure and training in the various TMEIC business units, he joined the global drives division, with a focus on application of engineered adjustable speed drives to large electric motors. His responsibilities include providing solutions-based engineered adjustable speed drives and motors, reviewing specifications, and technical and sales training for a wide variety of industrial clients and channel partners. He is a senior member of IEEE and has authored and presented more than 20 technical papers and tutorials for several conferences and seminars that enjoy a distinguished reputation and are nationally acclaimed.

Article written by Manish Verma of TMEIC and compiled by Newsletter Chairperson: Payal Majumdar. Let us know if you would like to be part of the newsletter team capturing events and sharing our stories.

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