Small motor load on transformer

[ENG1985]

Hello all,

I am new here and also new in the electrical field.

I guess I am just looking for tips, formulas, or maybe rules of thumb that some of you experianced people have out there that could help some of us newbies out regarding sizing single phase distrbution transformers for smaller motor loads (compressors for example) say up to 10HP. This would be with 200 or 400 AMP entrance.

This has got to be the most interesting, informational engineering forum I have found out there - I wish I would have found this sooner!!!

Thank You for your responses!

eng1985

 

[jraef]

If you can get yourself a little freebie book from an EASA (Electrical Aparatus Service Assoc.) motor rewind shop called the "Electrical Engineering Pocket Handbook", it has a handy little chart on recommended treansformer kVA ratings based on motor sizes. It only goes up to 7-1/2 HP for 1 phase motors. Unfortunately it doesn't say what the source of that chart is.

Just out of curiosity though, if you already know it is a 200A or 400A service, that would imply that you already have the service so what is the transformer for?

"Venditori de oleum-vipera non vigere excordis populi"

 

[ENG1985]

Sorry I meant meter base size.

Thanks for the info on the Pocket Handbook - I will see if I can get a copy of one.