Inverter current higher than input current (New Year’s Eve issue) Can inverter current to the motor be higher than the rectifier input current?That is a question that puzzles some people. Let’s have a closer look in our year-end post inverter current higher than input current. The recent advancements in VFD Read more…
Locomotive SKODA ES 499.0 (350 series) This article presents locomotive SKODA ES 499.0 (nowadays 350 series). It was a crown jewel of back then Czechoslovak Railways and despite its age of over 40 years remains operational until today as four-axle express locomotive. Background of locomotive SKODA ES 499.0 Concept of Read more…
AC versus DC drive For decades DC drive was a preferred choice for variable speed motors due to its easy and accurate way of speed or torque control. However, the development of AC drives changed the competitive landscape and paved the way for AC drives. What was the reason for Read more…
Merry Christmas We would like to wish all our customers, partners, supporters and friends a Merry Christmas. Thank you for joining us on our journey through 2020. As the world is getting faster and faster, we hope that you can slow down for a while, enjoy time with family and Read more…
VFD safety functions In this article you will read about VFD safety functions, their importance and principles. Safety is on top of the agenda for most companies, at least in all developed countries. One top manager calls safety one of the key elements for the “license to operate”. VFDs and Read more…
VFD as soft starter Welcome to the next article in our motor starting series. This time we will talk about VFD as a soft starter. Our first post focused on direct on-line motor start as the cheapest and simplest method. The second article provided a brief overview of common motor Read more…
Part 2: Overview of motor starting methods Electric motors as work horses of the industry are extensively used since decades. The topic of motor starting is therefore well known and various starting methods had been developed. This article presents an overview of most common motor starting methods. Which solution to Read more…
Part 1: Direct on-line start This series talks about solutions to start larger medium voltage motors. Aspects such as effectiveness, cost, impact on the supplying grid and driven load or effects on the motor design are taken into account. Article at hand describes the simplest solution: motor direct on-line start. Read more…