Equipment sizing guidelines
Equipment sizing guidelines
(OP)
Recently I have gotten myself into sizing medium and low voltage switchgear and I have several questions.
Where can I find some good general sizing rules for switchgear, such as:
- Bus sizing taking into consideration MCC loading and other sources.
- Tie switch sizing in main-tie-main configuration.
- General rules when it comes to transformer sizing, such as how low is too low based on projected load.
I know much of it deals with how much HP and load is connected and how it is used.
Is there a good book, or a website that can make this a bit easier to understand, or does it mainly depend on the engineer designing the system?
Where can I find some good general sizing rules for switchgear, such as:
- Bus sizing taking into consideration MCC loading and other sources.
- Tie switch sizing in main-tie-main configuration.
- General rules when it comes to transformer sizing, such as how low is too low based on projected load.
I know much of it deals with how much HP and load is connected and how it is used.
Is there a good book, or a website that can make this a bit easier to understand, or does it mainly depend on the engineer designing the system?






RE: Equipment sizing guidelines
Not just a good idea, It's the law.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Equipment sizing guidelines
RE: Equipment sizing guidelines
RE: Equipment sizing guidelines
RE: Equipment sizing guidelines
Other than that, the only sizing complaints I ever heard or had were about things sized too small. Usually sized for the initial construction plus some minor amount. Things like a 600A MCC ('cause that's the smallest they come) fed with a 60A feeder when the code minimum would have been 50A. No spare capacity and no long term value to the owner.
RE: Equipment sizing guidelines
I'm still curious if there is a good design book out there that would go into some detail on a good way to calculate this stuff.