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NEON- Power factor & Load Current



In my never-ending effort to better understand the functioning of
transformers, I came up with several questions today.  Any feedback would
be great.

I was working with one of the installers re. a channel letter job.  He was
determining the load current of the transformers so that when installing on
the building, they'd be able to properly load the fuses to the sign.  He
was using Table 6-4 on page 101 from Miller to do this.

Now, here's where my questions come in.  There was some discussion as to
which of the tables to use.  Initially, I was understanding that we should
be using the table for "Uncorrected Power Factor," but after some
challenging, I was beginning to be unsure.  I went back and read the
section on Power-factor Correction (pg. 62) and became more convinced that
I was correct.

I guess part of my confusion is in the different terms that I've heard
used.  From what I'm understanding, the table that is referring to
"Corrected Power Factor" is speaking of what we've called strayfield
transformers.  And the other table, "Uncorrected Power Factor," is
referring to "standard type."  Am I correct here?

So, following this, what I understand is that only the uncorrected power
factor/standard type transformers are available in the US and we should
clearly be using the table for "Uncorrected."  Right?

If so, I was also wondering why we aren't using those with a corrected
power factor.  I recall seeing the capacitors that were added to
transformers in The Netherlands and I think I'm finally starting to
understand the concept.  Or am I?

Tom U.

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