"Don Foreman" wrote in message
...
On Wed, 10 Aug 2005 10:34:51 +1000, "John G"
wrote:


"smitha4u" wrote in message
groups.com...
I believe i can bulid in my school lab.
Aprreciate if you can expalin it in detail
Thanks
Rgards
smitha


This is not a job to be undertaken by someone who has to ask such
basic
questions in a METALworking group.

It is proper engineering job for an experienced consulting engineer
with
experience in this type of indstallation.

How do you suppose engineers become trained to do such consulting?
That's why schools have labs.

I'm glad there are still students working with real machines in a real
laboratory rather than with 'puter sims. You can't simulate the
experience of a 50 HP DC motor drawing a gazillion amps of armature
current at stall, or if the field comes loose. Ya gotta see it in
person, after duly noting the motor bits still embedded in the bricks
from previous oopsies.

Unscheduled experiment: how fast can a twit lab TA dive under a
bench? Open field on big DC motor running with rated armature
voltage, time the twit when he hears it accelerating rapidly toward
kaboom. (Do close the field pretty quick. Forget about killing
armature current at that point; opening the switch results in a big
green arc)

The show is well worth the ensuing loud lecture endured with
simulated contrite humility. Your grade may partly depend on the
quality of your simulation....

Yes students do need labs with big machines and yes they do leave an
indelible impression .

Many years ago I was in a lab group that shut down the whole Physics
school of a large college 3 times doing an experiment with a big machine
where a careless technician (not a student) had reversed the wiring of a
Synchroscope. but the lab was designed and built by experienced
engineers and so no-one was hurt.
The OP in this thread is asking questions that are obviously beyond his
current (sic) level of expertise and this is not the place to learn that
sort of stuff.
He will get bits and pieces of advice and never know till after the fire
that he didn't ask all the relevant questions and so did not get all the
answers.


--
John G

Wot's Your Real Problem?