Re: Power

["Jason Johnson" <hvjjohnson13-at-xxxxxxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

> > Number 6 will easily handle 40 amps.  I'd go with a run of 8/3 myself
> > so that you could have both 120 and 240 available via a garage subpanel.

I'm running 6 guage because I already have all the wire. It was given to me
by a friend of my dad's whose work was throwing it away because the spool
was broken!

> >
> > >Also, I noticed that all the power comes into our house through a 5 KVA
> > >pole pig, and two 16/3 cables with the conductors parelleled.

Sorry my bad. I was going by memory but I actually got up on the roof today
(I'm still soaked from the rain) and looked a little closer. The two 16/3
cables are in the same place but bring power to the garage. There are also
three 2 guage aluminum lines that run to the main breaker panel in the
house, but are not as visible (when I looked the other day I was on the
ground and from my angle I could only see the 16/3 cables.) It is only a
5KVA transformer on the pole but they are built with a large safety factor
and it will have no problem providing power for my short-ish runs.

> >
> > Whoa!  Something's not right there!!  I think you best have an
electrician
> > take a look at your service before doing anything.  For one thing,
unless
> > your power usage in the house is just for lights, I don't see how the
16/3
> > has not burned up!!  I use a moderate amount of power here, about 25 KWH
a
> > day, and my home is powered from a dedicated 25 KVA pig with 4/0
conductors
> > running into the service panel!  Be safe and get it checked out.
> >
> > 73, Weazle, VE3EAR/VE3WZL
> >
> > Listening: 147.030+ and 442.075+
> > E-mail:    weazle-at-hurontel.on.ca
> >            or ve3ear-at-rac.ca
> > Web site:  www.hurontel.on.ca/~weazle
>
> Well, the NEC has lots of different tables on ampacity, depending on what
sort
> of conductor you propose to use and exactly what voltage drop you are
willing
> to tolerate and exactly how hot the conductors are permitted to get and if
they
> are copper or aluminum.  However, number 6 is pretty safe at 50 amps, all
other
> things being normal.  On the other hand, 50 amps times 240 volts is 12
KVA,
> give or take a square root of 2.  Forty amps times 240 volts is 9.6 KVA,
give
> or take a factor of square root of 2.  It would seem that perhaps you may
be
> blowing your house main breaker on a regular basis

That shouldn't be a problem. I'm running a seperate box (a 70 amp unit with
a 40 amp breaker for my work) with breakers in it out to the garage; it will
be in parrellel with the main box. Also this circuit will be kept off most
of the time and hardwired into my control unit. The control unit consists
mainly of a 660 volt 60 amp contactor, a Staco energy products 5021CT variac
rated at 7.8KVA (already know it will take the 40 amps for short periods), a
key switch and a emergency cutoff switch.

, if you are indeed using all
> of the amperage permitted by the laboratory conductors.  Perhaps you may
wish
> to turn off your lamps and your refrigerator before activating your coil.
>
> On the other hand, what the heck!
>
>     Best regards,
>     Bill Graves
>

I apoligize for causing such a stir, and I know that this wiring thing will
get done right.

Jason Johnson