![]() ![]() NEC is very rigid on load calcs for residential and works reasonably well. And assuming HP plus 5 times the largest motor (LRC Code F) is true if you can space out motor starting and ignores the fact that you can easily overload transformers quite a bit temporarily so they will be oversized. if I start on a soft start they often assume 3x FLA which is valid with a pump but in a crusher it’s 6x FLA. Just taking say a quarry crusher for an example most spreadsheets ASSUME LRC Code F. Online calculators are just too simplified. That’s where you need to have an estimate of %Z, LRC Codes, application settings for soft starts/drivesand a better transformer calculation that calculates %VD. It’s only when you do kw/amps conversions that the single phase sheet fails.įor transformers and generators the starting current often drives everything. If it does it purely in amps you could use a single phase calculator because the results are the same. When sizing as a load calculation it is fairly straight forward. ![]() ![]() The big problem with three phase is that in commercial you will have to keep track of 3 single phase loads and in industrial motors drive everything. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |