EMA Inc. | Norcross, GA | Tech Articles

Changes in the Siemens MV VFD Brand Family

Over the past 10 years, EMA has been heavily involved with repairing and servicing Medium Voltage VFDs. The most common drive we service, both in the field and in our repair shop, is the Siemens Perfect Harmony MV VFD. The Siemens/Robicon Perfect Harmony Drive was the first successful voltage-source medium voltage VFD in the industry. The H-Bridge design uses low voltage, single-phase output power modules cascaded together to generate medium voltage using low voltage power components. This simple and inexpensive…

How Remote Monitoring Medium Voltage Drives Saves Time and Headaches

There is never a good time for a Medium Voltage Drive to fail. Does this scenario sound familiar to you? Your Medium Voltage Drive fails in the middle of the night, your on-call technician, although very sharp, is not a VFD expert, everyone at the manufacture’s tech support is asleep, and the drive’s fault code has you scratching your head. Before the days of remote monitoring, this scenario would cost your production days or even weeks of downtime as you…

Medium Voltage Drive with DriveScan running

Why Remote Monitoring Your Medium Voltage Drives is the Superior Method

If you have medium voltage drives, then you know how challenging it can be to monitor, take readings, troubleshoot, and get them back online when a failure occurs. In this article, EMA’s Trey Mayfield discusses the shortcomings of widely accepted traditional methods and how you can save yourself a lot of headaches, time, and money with a new method using a remote monitoring solution. Why Existing Drive Monitoring Methods Aren’t Good Enough Medium voltage variable frequency drives are complex pieces…

DriveScan – The New Remote Monitoring Solution for Medium Voltage Drives

We’re excited to announce that EMA has formed an exclusive partnership with Powerside to develop a fully integrated, remote monitoring solution for medium voltage drives. Powerside has long been established as leaders in power quality and conditioning, which makes for a perfect marriage with EMA, the world-wide leader in medium voltage drive service. We bring over 50 years of combined experience to the development of this product. The product, called DriveScan, remotely monitors many aspects of your medium voltage VFD,…

Medium Voltage Drive Powers Cells: Refurbish, Repair, Replace, or Roll the Dice

As we’ve recently outlined, there are many factors that contribute to medium voltage VFD power cell life. With care and planning (or a preventative maintenance program), your electrical equipment can last a long time. However, there is a stark reality to all electronics: eventually, they all fail. The question many maintenance managers find themselves asking is, “What measures should I take when it comes to extending the life of my medium voltage VFDs?” Depending on your budget, time frame, and…

What Affects MV Power Cell Life?

Unlike low voltage variable frequency drives where the topology is consistent from manufacturer to manufacturer; medium voltage variable frequency drives come in a wide variety of topologies. The majority of medium voltage VFD manufacturers utilize some sort of power cell technology in their drives. By making the output section modular, the user is able to get up and running quickly by simply swapping the power module instead of troubleshooting down to individual components within that module. The design varies a…

EMA Is Celebrating 30 Years In Business Thanks To You

Thanks to you, EMA is celebrating 30 years in business! The only reason we exist is you, our customers, and we never allow ourselves to forget that. We don’t take our longevity or success for granted and appreciate that past successes do not guarantee future results. That is why we continue to work hard every day to fulfill our motto that “No One, Anywhere is Better at Drives than We are.” When thinking about the fact that we’ve been in…

Yes, we STILL repair Stromag (Drivetronics) Drives

EMA is the only authorized distributor and service center in the USA for KEBA-LTi (LUST). We have been selling and servicing their drives for decades. In 2001, LTI acquired Stromag Elektronik GmbH. Stromag drives are found in Metal Fabricating Machines all over the globe. EMA has seen a steady increase in Stromag drive repairs over the last few years especially since factory support has long since ended. Oftentimes, it is not economical to repair small AC drives in standard applications;…

York MVVSD Repair

York MVVSD (Medium Voltage Variable Speed Drives) series drives are used on large, medium voltage York chillers, in ranges up to 10,000 horsepower. It is common to see VFDs used in low voltage chillers and compressors, but due to decreasing costs of electronics, medium voltage VFDs are becoming more common because of the potential energy and mechanical savings on medium voltage chillers and compressors. For further information on how VFDs can save energy on variable torque applications, click here.…