anyone want to help me with my presentation?

[big2bird]

Er, a no Gene.:suicide:

 

[turtlevette]

normally a unit transformer is connected delta on gen side to grounded wye on the HV side. The generator is high impedance grounded through a transformer with an impedance connected across the other winding. The high impedance limits ground faults to only a few amps.

With ground faults no threat for damage, the connection to the unit transformer is through isolated phase bus. Each phase bus has a grounded tube around it so there is no possibility of a phase to phase fault.

 

[mrvette]

Jim, could you esplain to me how a single transformer's iron CORE is configured when the input is 3 phase..?? I can't grasp how that would be done to keep the phases from cancelling for 120* and maybe, yes?, drawing too much current on account of it....the thing can't be a EI lamination type thing the way my mind works, single phase....

for Bird...early 80's Walk through metal detectors for airline/industrial/prison type security....had a line of our machines at Duke Power in NCar. somewhere, Nuky plant.....so every so often the whole damn line of them would go off and start ding a linging on their own....no reason, just happened....we shipped whole new units...no go....this when the movie Ghost Busters was only a year-2 old.....

we sent engineers, me as field tech rep, and even a physicist with nuclear background, as well as their plant manager and physicists/engineers....

we spend 3-4 days searching for the cause, come find out it ONLY happend on a cool /dry day....usually winter....but if it was raining, snowing, higher humidity everything was normal....

so one day a guy showed up a bit late for work, getting out of his car in the 5th floor down level, he had a loose exhaust system....reaching for his pipe to look at it, he got a living **** burned outta his arm.....just laying on the ground.....it was one of those ding a ling daze (as we called it)....

SO upon that happening, they found out they entire plant was NOT GROUNDED....the what they say?? 25? 50kv? 3 phase lines coming in overhead off the grid from several hundred miles away...the plant was floating, no ground....

when the head engineer who I shook hands with saying please calll ME, when/if you EVER find out WTF is going on here.....

so a YEAR later he calls and tell me of the plant being ungrounded....

my reaction was stone silence.....he asks hello, you still there??

I said yes, but i'm trying to absorb what you just said....he laughed and said you heard it".....

I asked what in the **** you do to ground a nuclear power plant??....

he says get the biggest well digger in Carolina, rig from HELL, drill clean to China, stick a bolt/rod from hell down through it, put a nut on each end, tighten securely and use the grounding strap from HELL ......

:lol::lol:

in those daze, it was known as Goodyear Atomic.....processing plant on the Ohio river...making bomb/plant nuky material fuel rods.....

they had power lines coming in from ALL the mountain tops surrounding the joint, I thought they were OUTGOING lines, and thought it must be a plant the size of the state....NO, they were INCOMING lines cause the old type process they using there needed large amounts of electricity to process the Uraniun into whatever.....

THAT plant was grounded through a gigantic wire mesh burried deep under the entire campus....miles in each direction....the copper was described to me as being about 2" diameter each wire/condustor/strand.....

so they just dug a hole, found the ground plane, tied into it and... case closed....

I LOVED that job, saw some crazy **** out there.....mind opening for sure....

and too boot it was FUN, not so much the travel, but the sites and people....

:smash:

 

[turtlevette]

Jim, could you esplain to me how a single transformer's iron CORE is configured when the input is 3 phase..?? I can't grasp how that would be done to keep the phases from cancelling for 120* and maybe, yes?, drawing too much current on account of it....the thing can't be a EI lamination type thing the way my mind works, single phase....

i'm not a transformer expert. There are 3 cores in there but they are connected at the top and bottom. The primary and secondary of each phase are on the same core. The cores are far enough apart to prevent any significant interphase coupling.

I don't know much about how the make the stuff, but mainly how to protect it.

 

[JPhil]

Sorry for the hijack, but I can't stand it that you guys don't know what the Philadelphia Experiment is....

http://en.wikipedia.org/wiki/Philadelphia_Project

and if that interests you at all, look into this one....


http://en.wikipedia.org/wiki/Montauk_Project

OK, back to our show.

John

 

[big2bird]

Gene, three phase trannys are wound on a laminated steel core shaped like an E with the ends closed. Ergo, "E" core. (Looks like a sideways 8)

 

[DARROW 74]

Where is that flux cap at, its missing again.

 

[mrvette]

Gene, three phase trannys are wound on a laminated steel core shaped like an E with the ends closed. Ergo, "E" core. (Looks like a sideways 8)

So they wound on the same E/I lamination I know as a typical power transformer?? only the E is alternated back one way and another interleaved and capped with one I between 2 heels of the alternate E lams...

so the other coils are wound on the outside legs?? are there any further extensions to the outside yet further...making maybe 5 legs on the E???

:huh:

 

[big2bird]

So they wound on the same E/I lamination I know as a typical power transformer?? only the E is alternated back one way and another interleaved and capped with one I between 2 heels of the alternate E lams...

so the other coils are wound on the outside legs?? are there any further extensions to the outside yet further...making maybe 5 legs on the E???

:huh:

No.

 

[mrvette]

Yeh, that was my first guess.....but trying to imagine the 3 phases and that flux path is just crazy....

:bonkers::shocking::shocking::shocking::banghead:

 

[saudivette]

Trying to understand what you're all on about...

...is just crazy....

 

[mrvette]

Trying to understand what you're all on about...

eh...you not a geek, so I understand your mind is limited.....:clobbered::goodevil: :shocking:

 

[BRUTAL64]

Where is that flux cap at, its missing again.

Hell, I thought you knew where it was.

 

[mrvette]

Hell, I thought you knew where it was.

It's beeing charged up good and tight, going to toss it at your guys someday....

:clobbered::bounce: