How to compare efficiency figures of drive systems? Just two important reminders before starting with the topic: 1) Always keep in mind that the energy savings come due to variable speed control. The load consumes significantly lower power when the Read more…
Derating and uprating factors What is the power rating of the specific VFD? An indicative value is provided in the technical catalog or brochure. This value shall refer to certain operation conditions, among others the temperature of cooling medium (air Read more…
How to choose a medium voltage VFD:Life cycle cost What is life cycle cost (LCC)? The definition from business dictionary (www.businessdictionary.com) says: Sum of all recurring and one-time (non-recurring) costs over the full life span or a specified period of Read more…
How to choose a medium voltage VFD:Engineering support Engineering support from VFD manufacturer significantly influences how smooth the execution of your project goes and how successful it will be in the end. It also directly impacts the quality of the Read more…
How to choose a medium voltage VFD:Protection concept A variable speed drive system with gaps in protection philosophy is a ticking bomb. It might have a huge impact on plant availability and potentially also on personal safety. Therefore, no compromises Read more…
How to choose a medium voltage VFD:Design robustness Every end user probably wishes that his VFD has a robust design and works as intended during the entire lifetime of at least 20 years. Unplanned shutdowns and outages are unwanted. But Read more…
How to choose a medium voltage VFD:Motor compatibility VFD – motor compatibility is an essential precondition for successful operation of power drive system. There is a large amount of publications underlying this topic. This article aims to explain the matter Read more…
How to choose a medium voltage VFD:Line side connection and power quality Nowadays modern VFDs offer large variety of line side configurations. Which one to select? That is the topic of today. There are two basic groups of VFDs based Read more…
How to choose a medium voltage VFD: Cooling type This post looks into drive classification according to cooling. Same as for instance electric motors also VFDs can be divided in two main groups with regards to VFD cooling type: Air Read more…
How to choose a medium voltage VFD: Application requirements The requirements of your application are key when selecting suitable VFD. If you check the websites of leading medium voltage VFD manufacturers you will find several products with different performance data. Read more…