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Mr. Luddite[_4_] Mr. Luddite[_4_] is offline
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Default Betsy displays some sense!

On 10/13/2018 5:15 AM, Mr. Luddite wrote:
On 10/12/2018 10:25 PM, wrote:
On Fri, 12 Oct 2018 19:03:59 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 3:07 PM,
wrote:
On Fri, 12 Oct 2018 14:34:56 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 1:10 PM,
wrote:
On Fri, 12 Oct 2018 08:00:23 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 1:04 AM, Bill wrote:
Mr. Luddite wrote:
On 10/11/2018 8:12 PM,
wrote:
On Thu, 11 Oct 2018 16:42:41 -0400, "Mr. Luddite"
wrote:

On 10/11/2018 3:40 PM,
wrote:
On Thu, 11 Oct 2018 14:11:23 -0400, John H.

wrote:


http://tinyurl.com/y7dezaq3

"The left is revving up attacks on capitalism just as
workers on the
bottom rungs are beginning to
benefit from the booming U.S. economy. According to last
week's jobs
report, unemployment has been
pushed back to its lowest level since 1969. Wages in
blue-collar
industries, such as construction
and maintenance, are rising faster than for white-collar
workers. Pay
for people without a college
education jumped almost 6 percent since last year -- triple
the overall wage gain."

Gosh, I thought wage growth was stagnant.

There was an article in USA Today yesterday talking about
.how wages
are going up across the board and some jobs are really
taking off

BTW your link took me to Harbor Fright generators.

About that, why is my 5.5 KW Briggs 11 hp and theirs is 8?
They must have stronger horses in China



With no losses considered:

8 hp = 5.96Kw
11 hp = 8.2Kw

I completely forgot about a small generator I bought from a
neighbor
last year.Â* It was brand new, still in the box and she
decided to have a whole house generator installed instead.Â* She
only wanted $200 for it but after looking it up I decided I'd be
ripping her off, so I gave her $300.Â* It's rated at 4,750
peak watts
and 3800 watts continuous.Â* Engine is 6.3 hp.

I put it together last spring and fired it up.Â* Ran fine, was
not
overly noisy (for a conventional type generator).Â* It has
electric
start which is nice and will run on gas or propane, although
propane
is at a reduced output capacity.Â* I ran it out of gas and
stored it away
and, until just now, had forgotten I had it.Â* It's a "Wren"
that she got
from Home Depot:

https://tinyurl.com/ybef4hty

I keep hearing about the reduced output capacity on propane but I
don't see it. I will say fuel consumption is where the
difference of
energy density shows up. At full load the gasoline consumption is
around 0.5 GPH and propane is more like 0.8 GPH although the
gasoline
is easier to measure accurately. I am just going on a gauge on
a 150
gallon tank and that is not very precise.
After a similar discussion on the real boat group I tested my
generator using my convection oven as the load.
This is 5402.7w running a 5500w generator on propane
http://gfretwell.com/Propaneproject/Onpropane.jpg
When I plugged in two 100w lights, it tripped the breaker
before I
could take pictures.



I think any generator can temporarily exceed their rated
capacity but
they may not last long if done on a regular basis.Â* Windings
and other
components will get hot and go "poof". It's not often that
generators
are running all the time at full capacity and if they are, you
probably
need a bigger generator.Â* :-)

I mentioned before that the little Honda I have is rated for
2,000 watts
surge and 1600 watts continuous or 13.3 amps.Â* It ran my large
microwave
with a measured amperage draw of over 16 amps for a short time
but as
soon as I realized how much current was being drawn I shut the
microwave
off.Â* I wouldn't do that on a regular basis.Â* The circuit
breaker on the
generator never tripped.

I've been looking around for a larger portable generator but I
want one
with 4 poles instead of the typical 2 poles. 4 poles will allow
the
engine to run at 1800 RPM to produce it's rated output at 60Hz
instead
of the typical 3600 RPM in a 2 pole generator.Â* 3600 RPM is the
main
reason they are so noisy.





My Yamaha 2000 runs my Samsung camper microwave fine.Â* Never ran
it for a
long time, mostly heat water for coffee.


The Honda 2000 runs the smaller, counter-top microwave fine as
well, but
it's only rated at 750 watts versus the 1200 watts that the over
stove,
built in microwave is rated at.Â*Â* I purposely shopped for the lowest
wattage small microwave I could find and 750 watts seemed to be the
smallest.Â* It still draws about 11 amps when running, so it needs
1320
watts of power to produce 750 watts of microwave power.Â* 1320
watts is
within the Honda's rated continuous output of 1600 watts.

That's the thing. Can't confuse output power rating of the microwave
with the input required to produce it.Â* The large microwave was
drawing
slightly over 16 amps to produce 1200 watts of microwave power.
That's
at least 1920 watts.Â* The Honda is only rated for 1600 watts
continuous
output and 2000 watts "surge".Â* So to run the large microwave the
Honda
was running near or at it's surge rating continuously.Â* Not good.




That should have a 5-20 plug on it if it pulls 16a. I assume it is on
a dedicated 20a circuit.



It *is* on a dedicated 20a kitchen circuit although I was wrong about
it's microwave output power.Â* It's 1000 watts, not 1200 as I had
previously thought.

As mentioned in another post the sticker indicates a service
requirement
of 120vac at 1.64 Kw.Â* Output is listed as 1000 watts.Â* So, it
draws 13.666 amps running ... I measured 14 amps on house power, 16
amps
(briefly) on Honda power.

So, on house power:Â* 1640 watts in, 1000 watts out.Â* Makes sense to
me.


640w of waste heat coming out the vent sounds high to me. The vent on
mine is barely warm. I had more waste heat coming out of my satellite
receiver.


What makes you think the extra 640 watts is "waste heat"?


Any energy that is not going to the load (food in this case) is waste.
You have to assume the radiated power *mostly* ends up in the food so
anything else is waste.
The first thing you need to know when you are computing the HVAC load
(heat) in a computer room is the power coming in. (AKA sensible heat)
It is roughly 3400 BTU per KH and you assume all electricity coming in
goes out as heat so you are saying your microwave is pumping 2217.89
BTU in the air the whole time it is running ... plus what it does
heating the food?

Sorry I was an Installation Planning Rep too ;-)

I really think if all of that was true you could cook another hot dog
on the fan.



Well Greg, the specs on the sticker didn't lie.Â* Input power required
is 120vac, 1.64 Kw.Â* Output: 1Kw.Â* Confirmed by current reading of
14 amps when the microwave is running.

I'll do another test.Â* I'll run it again monitoring the current but
set the microwave power to 50 percent or so.Â* All that does is cycle
the magnetron on and off for a 50 percent duty cycle.Â* I'll see what the
current draw is when the magnetron is in it's "off" cycle.





Ok. Did the above described "test". With the magnetron running
the current draw is about 14 amps (bounces from about 13.8 to 14.1)
When the magnetron shuts off but the microwave is still running
the current drops to about 0.8 - 1.0 amperes. The fan, turntable,
internal light and control/display are still running.

So, when the fan, turntable, light and control/display are on, the
microwave is consuming about 108 watts (0.9a * 120v) of the 1640 watts
service rating.

The magnetron, when it kicks in, is using an additional 13 amps or
about 1560 watts.

108 watts plus 1560 watts = 1668 watts. Damn close to the service
rating of 1640 watts. I attribute the 28 watt discrepancy to
the accuracy of the Kill-a-Watt meter and the number I noted
as it ran. The current readings tend to bounce around a bit.

Each of the powered devices (the turntable motor, fan, light,
controls/display and magnetron) are not 100 percent efficient
obviously so there are losses in each that are given off in heat
but the numbers are pretty close to the sticker reading.
Obviously, the losses don't add up to 640 watts of "waste heat"
going out the vent, so that's why you can't cook a hot dog on it.

Thus ends my science experiment for the month. :-)