Locked-Rotor KVA Code (Letter)

Determine it? It is something that is required to be on the motor nameplate.

So then this is something that can't be indicated until the shop drawings are submitted for the motors?

Essentially, yes. Here is what I was talking of.

http://www.arescobuyersclub.com/nameplates.html

The kVA code letter is required to be on the nameplate. it either says "kVA Code" as in the above example, or sometimes "NEMA Code" or even just "Code", but the data must be on there for NEMA design motors.

But you technically could specify a particular code number, or a 'not to exceed" value if you are planning a project. if so, and you don't know where to start, select a motor from a manufacturer that you are confident will work, then see what their Code number is and specify it.

I'm not sure if this is what you're looking for, or if it will help you any.

http://www.engineeringtoolbox.com/locked-rotor-code-d_917.html

NEMA table 430-7(b) outline the Locked-Rotor Code Letter.

Lock Rotor code is about ratio of kVA/hp. As you know kVA = √3 *V*I, and HP you know it as well. So, find this ratio and give to your asker, instead of code letter if you don't have NEMA table 430-7(b).

cheers

It is KVA per hp under locked rotor conditions.NEC code starts wit a to V a for example stands for 0-3.14, B for 3.15 to 3.54 these are kva per hp values.

1) That is as per Standard NEMA, and was built starting the motor wih nominal voltage and and having bloked the rotor. As motors are built by many manufaturers and as for example a 2 HP IEM motor will have a different starting curren as a 2 HP ABB motor even if they are of the same motors class(they have different starting current because they do not have the same impendance). That is the reason a code letter has a range of values.

2) The code letter A is for small motors and so on for bigger motor B,C, D, etc.