wye-delta starters

[phillyg]

can someone explain the operation of a wye-delta closed transition starter? What is the function of the "shorting" contactor; and what are the resistors used for? Thanks in advance!

[Tom R]

phillyg:

Try this web site it will explian it better than I could.

http://www.lmphotonics.com/star_delta.htm

[freonrick]

you will need a diagram and a sequence of what is going on. the shorting of the contactor is actually reconfiguring the motor windings. I could not explain it here. try to find someone to go over it with you with the diagrams.

[hvac3901]

Now i thought that primary resistance starting and a wye-delta starter were two different animals.

[mancuso jr]

No Primary Res. Starters are different in that they use Res. moment to limit inrush then close another contact for full voltage , you could say they are more related to auto transformer starters than y-delta.

[absrbrtek]

Due you work with J. Fusco?

Originally posted by mancuso jr
No Primary Res. Starters are different in that they use Res. moment to limit inrush then close another contact for full voltage , you could say they are more related to auto transformer starters than y-delta.

[Carrene #2]

The resistor bank on a closed transition Y Delta starter, actually carries the load during the "closed transition". This will produce less arcing as the the contactors make and break. They are in the circuit for less than 1/10 th of a second. If this takes longer, the incomplete transition fuse blows ( or brakes depending on your terminology ), somewhere in the 1/10 of an amp. fuse.

[Edited by r718 on 01-20-2006 at 08:56 PM]

[phillyg]

No Abs, I don't know J. Fusco

[airworx]

we installed 4 120 ton york air cooled screws. when units would start up they would go off. we found the cover plate of some of the starters that cover the control voltage connection had fallen off inside the starters preventing them from switching. i thing they would go off on high start amps. but just giving yall a heads up.

[Tom R]

Hey Guys:

I retired 10 years ago this month so I am out the loop on what is current.

Are they still shipping new stuff with wye/delta?

I would have thought that by now solid state starting technology would have pretty much replaced most of the other reduced voltage starting methods.

Thanks for any input. Tom

[gkt1937]

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[gkt1937]

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[gkt1937]

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