Transformer Info

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Dennis Alwon

Dennis Alwon

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First off I want you to know I do not know anything about trany's.

I ran into this and don't understand it.

What is the current on the secondary side of a 75 KVA 3 phase 480:208/120 volt wye transformer?

What does the 480:208/120 mean?
 
Dennis Alwon said:
First off I want you to know I do not know anything about trany's.

I ran into this and don't understand it.

What is the current on the secondary side of a 75 KVA 3 phase 480:208/120 volt wye transformer?

What does the 480:208/120 mean?
Click to expand...

The secondary current is 208 amps (75000 va / 208 volts / 1.73 sq rt3 = 208 amps).

The ratio shows the primary voltage as 480, the secondary as 208 line to line, and 120 line to the midpoint of the wye secondary.
 
Thank you-- I couldn't understand the colon. I was thinking it was a 480 or 208 tap on the primary and 120 on the secondary but obviously that was dumb thinking. That also explains why I got the wrong answer. :grin:
 
cadpoint said:
One of your signature statements serves you well! A colon expression of a ratio!

:grin:

http://mathworld.wolfram.com/Colon.html
Click to expand...

Yeah I know what a colon is. Someone was here with me and somehow I just look at it in a bizarre way. Again I'll blame the drugs but to be honest I had never seen a trany written as a ratio. Obviously I am a bit inexperienced with tranys. Except for a few door bell transformers I believe I have hooked up less than 3 in my life and all of them were very small.:grin:

And Jude-- I am good at fractions....:grin: I am also good at sarcasm
 
Dennis Alwon said:
First off I want you to know I do not know anything about trany's.
Click to expand...
A transformer is used to transfer energy from one circuit to another. It can provide isolation between the systems and a change in voltage levels or both.





















:grin:
 
LarryFine said:
In this case, it replaces the word "to".

A 480 to 208Y/120 transformer.
Click to expand...

Yes, I still cannot believe I didn't see that but hey- c'est la vie.

Thanks -- just when I think I have gotten real good at this code stuff I always get put in my place.:grin:
 
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