On 10/12/2018 2:36 PM, Keyser Soze wrote:
On 10/12/18 2:12 PM, wrote:
On Fri, 12 Oct 2018 11:02:06 -0400, Wayne.B
wrote:
On Fri, 12 Oct 2018 08:23:18 -0400, Keyser Soze
wrote:
I happen to have that info handy because I looked it up last week
when I
had to replace a dead microwave oven. Here's how it is figured:
A 1200 watt output microwave takes 10. The typical formula for this
is..
P = VI.. I = P/V = 1200 /120 =10 A. Hence, one would think that the
answer is 10 A.. However, this formula applies only for DC current. For
AC current,. P=VI cos (theta). where theta is the phase difference
between V and I.. This phase difference is created by the inductances
inside the microwave oven.
===
Whoo hoo!Â*Â* 'Airree discovered Power Factor, well known to EEs of
course,Â* which is why most high powered AC electrical devices are
rated in KVA instead of KW.Â* For bonus points explain why inductors
create a phase difference between voltage and current.
I was going to say something about that but I am just a high school
graduate so Harry would think it was bull****.
I imagine he thinks the left/right hand rules are just about whether
he is fantasizing about Selma Hayak or Scarlett Johannson.
Even we dumb assed electricians know about power factor. The only time
it usually causes a problem is in 3 phase wye neutrals (triplin
harmonics)
This is something I would find worth knowing because...
Damn, I can't think of one reason...
When I need home wiring advice, or heavy appliance advice, or serious
plumbing advice, or repairs or new service in those areas, et cetera, I
call a licensed tradesman or contractor.
Electrical I can handle because I've had some education with it although
it was in electronics, not electrical. But, I had to study a bit and
learn more because of the industrial equipment my company built. Not an
electrician but, as an engineer I am usually more conservative that what
even the code book calls for.
Plumbing is another story. I just don't have the knowledge or patience.
Done properly, electrons don't leak. Water does.