> Wouldn't the best thing to do is to ask the engineer that gave JoAnn
> these
> rules why these rules are important to him?  His intentions for this
> conformity
> may be completely different from what every one is trying to guess.
>
> just a thought
>

That's actually a good question but the "product" engineer  (2 yr degree) who
gave me that rule is not the "project" engineer (4 yr degree) who designed it
originally.  I've asked others here the same question and apparently this was
the *old way of thinking* and no one ever told him that those guidelines were
not necessarily applicalbe.  Information is often hard to come by and reliable
information darned near impossible.

I solved the problem by laying it out as best as I knew how, minimizing trace
length where possible.  As I said, I'm a newcomer to this field and am just
learning how to size traces based on current load/weight of copper/rise above
ambient temp.  Now we are getting into complying with IEC1010 - ARGH!  It is
not an easy job.  Our agency rep is revising the clearance/creepage tables
every day (usually twice a day) and we are all trying to second guess UL.
Anyone else out there having this much fun?



JoAnn L. Amerson
Design Librarian
Red Lion Controls, Inc.
E-mail: [log in to unmask]
Voice: (717) 767-6961 ext 6308