Wye start Delta Run

[GoldDigger]

No it's not, 230 volts is the rating of the windings, standard NEMA motor voltage rating just as 460v is, the 1.732 is off the voltage that would normally feed the motor 240 volts or 480 volts, but I see he has 208 volts so take 208/1.732 to get what the windings will see or 120 volts across each winding, which I'm not so sure a 12 lead motor should be WYE started on a 208 volt system, as the motor might not have enough torque to start? but should run find as a across the line start motor if its not a high torque application.

Which of these three is not like the others?

1.732 less than 240 is 238.268; 1.732 less than 230 is 228.268.
240 less 1.732 is 238.268; 230 less 1.732 is 228.268.
A factor of 1.732 less than 230 is 132.8, while a factor of 1.732 less than 240 is 138.568.

And, just to confuse things:
A factor of 1.732/2 times 230 is 200. A factor of 1.732/2 times 240 is 208.
( It gets more ambiguous if you leave the Volts out everywhere instead of just in some places.)

 

[hurk27]

You are too serious man.

You said: but later said they will see 138.57.

I said (in other words): 230 - 1.732 = 228.268.:thumbsup:

Yep I did that, I admit to it, I mean I won't try to lie, I did say that:happyyes:

Did I say that?:lol:

I need a life LOL

I've been having to much fun playing with my new Toyota Rave4, went up to Silver Lake State park on Lake Michigan about half way the west coast of Michigan with it Saturday, had a ball climbing the sand dunes, it has full lock up transfer case and axles with a auto six speed tranny, could not believe what that car would go through, today took a ride down to Kankakee river wild life park, its just so fun to drive, and much better then sitting in front of this computer LOL.

So I guess my mind is not really in my post as it should be:blink::ashamed1:

 

[hurk27]

Which of these three is not like the others?

1.732 less than 240 is 238.268; 1.732 less than 230 is 228.268.
240 less 1.732 is 238.268; 230 less 1.732 is 228.268.
A factor of 1.732 less than 230 is 132.8, while a factor of 1.732 less than 240 is 138.568.

And, just to confuse things:
A factor of 1.732/2 times 230 is 200. A factor of 1.732/2 times 240 is 208.
( It gets more ambiguous if you leave the Volts out everywhere instead of just in some places.)

Yea I get the point, guess you and Kwired is going to have to keep me inline

 

[kwired]

I'm pretty certain you will get me back sometime. I kind of asked for it in a way.

 

[robbietan]

If you are controlling the motor with simple across the line starting method, you connect it according to the "run" diagram. If you have a situation where the POCO wants you to start this motor with starting methods that will reduce the starting surge then you either need soft starter, VFD, part winding start controller, or wye - delta controller. It sounds like you have a motor designed to connect to wye - delta controller. Such motors will still start on full voltage across the line - but the type of driven load or the POCO may help determine if wye-delta starting is necessary. But often times many POCO do not require any special starting methods for a 25 hp motor, you usually have to get into the 50 or 100 HP range before they start to get concerned about your starting methods.

different here in my neck of the woods. usually a 5 HP motor is enough for the POCO to require a reduced voltage starter scheme

 

[kwired]

different here in my neck of the woods. usually a 5 HP motor is enough for the POCO to require a reduced voltage starter scheme

Apparently they don't put any $$ into building infrastructure, this is 2013 last I knew and not 1930. Anyone with a 5 ton or larger air conditioner would need reduced voltage starting

Around here there is irrigation pump motors all over the place - most between 60 and 100 hp and all are across the line connected. The local POCO recently decided that anything over 100 HP needs to have reduced current starting methods, but there are some older 125HP well motors around that are also across the line. Only reduced current starting method I have ever seen that was required was for 250 HP - it was part winding start setup. I've installed a few soft starts but not because POCO wanted them, but rather the customer, designer, etc. wanted them, usually for less shock on the driven load at startup.