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Re: Preventing a REALLY expensive mistake.



Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-uswest-dot-net>" <jimlux-at-earthlink-dot-net>

> 
> 1. The building is fed with 1-P 240VAC, and will be upgraded to 3-P 480VAC
> (for the elevator of doom), should I keep the 1P service as well? or just
> have the landlord upgrade from one to the other?

Presumably, when they bring in the 480, they provide local transforming
down to standard 240/120?  Otherwise you'll have to do it yourself.  

If it doesn't cost anything, I'd leave the existing service in.

> 
> 2. Will a system of 10 seperate 8-10' ground rods driven vertically around
> the buildings exterior and all laced together for a massive ground system be
> an good enough protection for the computers and other electronics? Is there
> a better way?
Not necessarily...
The key is to keep your electronics grounds separate from the power grounds
(hence the prevalence of those orange Isolated Ground receptacles) until
you get back to the common panel ground.  If you don't make loops, you're
less likely to pick up noise.
> 
> 3. What are all the steps I CAN take to ensure the safety of our computer
> systems? I have to assume that the computers will be operating at the same
> time as the coils (and other HV gear), since as we all know, all Micro$oft
> NT-5 systems maintain 99.999% uptime and are virtually error free.....at
> least that's what the slicks tell us. 'Course, if you believe that I've got
> a great deal on some property in Florida for you, the everglades, perhaprs
> you've heard of them?

Run the sensitive loads off an isolation transformer. 

> 
> 4. I remember reading about garage coilers who have had discharges through
> the roof, can this happen on a solid concrete structure? (There will be
> classrooms under the H.V.L.)
Concrete may or may not be a good conductor.

> 
> 5. I've heard of coils being mounted inverted from the ceiling. How is this
> done? Why? What are the advantages of this setup? Can it be used to make
> near vertical discharges to the floor?

Talk to Jeff Parisse..
> 
> 6. Will the operation of large amounts of HV gear cause a signifigant rise
> in the static electricity of the entire building? I'm worried about the
> hardware labs, static and CMOS devices aren't exactly friendly with each
> other.

Nope.. you're basically worried about EMP type things, not ESD.

Take a look at literature from the various lightning protection folks, like
PolyPhaser.