Re: terminology help for newbie (pleeze<=)>

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "BunnyKiller by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bigfoo39-at-telocity-dot-com>

Tesla list wrote:

> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jbdetails-at-prodigy-dot-net>
>
>    I am new to the technical side of electronics so sometimes terms
> used are a little confusing. Could someone possibly point me towards
> a web site or explain to me what "MOV, Coupling, KVA, and maybe
> somewhere that explains AC motor speed control. (specifically a 1/3hp
> AC motor that has windings around the rotor, no windings in the
> rotor, and doesn't require a capacitor)
>
> Thanks,
>     Bob Bozarth

Hi Bob...

for some quick answers

MOV = metal oxide varistor  in other words... a "spark gap" designed for a
specific
voltage.. if the system developes more voltage than the MOV is rated for,
the MOV will
provide a path to ground for a brief instant diverting the hi volt spike to
ground...

coupling is the amount of magnetic field transference from one coil to
another ( as in
transformers etc) the higher the number the better the transference...

KVA  = kilo volt amps   kinda like watts   if a you have a 10KVA unit (
10,000 volts) and
it is capable of handling 1 amp   likewise if the unit runs at 500V it is
capable of 20
amps    ( V times A = KVA/1000)  thus ...  250V -at- 10A = 2500VA or 2.5KVA
you can use the
KVA rating to find out how much amperage a unit is capable of too   lets
say you found a
variac rated for 240V and it sez on the name plate 8.5KVA...

8500/240= 35.4sumthing amps  thus the unit is designed to handle 35 A -at- 240
output...

sounds like you have an inductive motor  solid rotor, wound stator...
pretty much a
standard motor.... AC motor speed control isnt all that simple as compared
to DC motor
speed..

best bet is to go to an electronics supply house and see if they have any
old catalogs
they are willing to get rid of ( out of date, defunct suppliers etc) let
them know you
are entering the exciting world of electronics and need all the help you
can get :)  they
normally will dump 100 lbs of catalogs in your lap...  great reading
material... lots to
learn....   lots to buy  ;)

Scot D