Is it more economical to buy low distortion loads or to apply harmonic correction?

A question that we often get is: it more economical to buy low distortion loads or should I buy a standard load with harmonic correction after the fact? 

The question of low distortion loads and system level fixes or harmonic correction after the fact really comes into play from an economic standpoint. And when you think about things like variable frequency drives, the question really is important to think about on a power system of many drives. For example, let's say you're in a water treatment plant and you have 10 drives and you're only going to run five drives at once. It probably makes sense to put a system-level solution in rather than to put a harmonic solution on every single drive or have low distortion drives and try to correct it because you're only going to run five instead of 10. In terms of things like computer power supplies, almost every server that you have in a data center now is going to be power factor-corrected or harmonically-corrected. 

So whereas the price was significantly different before. The new ones were… let's say you went from a switch mode, power supply that was $15 to a power factor, corrected power supply that was 75, the price differential isn't that significant anymore. So getting a corrected one is much more economical rather than trying to correct it on a system level with your transformers, double size neutrals and everything you have to deal with at that point. With a UPS system and other systems like that we've talked about in some of the FAQs, it makes more sense to buy that as a low distortion load, rather than to add in additional filters because the actual IGBD front end on a UPS gives you additional benefits. Other things to think about if you're specifying a rectifier, let's say for vehicle charging or maybe four forklifts. It really depends on if it's a small load on a big system, or if it's a big load on a small system. As an example for drives, if you were going to use drives that work for maybe 250 horsepower, you probably want to look at an 18-pulse drive as opposed to buying the drive, buying a harmonic filter, putting the two together and the cost that's associated with the installation of everything, because at some point is diminishing returns in terms of trying to get the same harmonic effect out of the add-on feature. 

So, drives 150-200 horsepower look at making the drive itself better from the start .18 poles, 24 poles, and other loads like directive fires and things like that really depend on if it's a small load and a big system, or if you have for lighting, for example, if you have a lot of those loads and it makes more sense to buy it up front, rather than trying to deal with it after the fact.