On Sat, 13 Oct 2018 05:31:57 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 10:36 PM, wrote:
On Fri, 12 Oct 2018 19:10:14 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 3:57 PM, wrote:
On Fri, 12 Oct 2018 14:56:36 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 2:04 PM, wrote:
On Fri, 12 Oct 2018 14:37:24 -0000 (UTC), Bill
wrote:

Mr. Luddite wrote:
On 10/12/2018 5:49 AM, John H. wrote:
On Fri, 12 Oct 2018 05:04:47 -0000 (UTC), 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. It was brand new, still in the box and she
decided to have a whole house generator installed instead. She
only wanted $200 for it but after looking it up I decided I'd be
ripping her off, so I gave her $300. It's rated at 4,750 peak watts
and 3800 watts continuous. Engine is 6.3 hp.

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

I mentioned before that the little Honda I have is rated for 2,000 watts
surge and 1600 watts continuous or 13.3 amps. 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. I wouldn't do that on a regular basis. 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. 3600 RPM is the main
reason they are so noisy.





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



Even the bigger microwaves are only about 1200 watts. Shouldn't be a
problem for the 2000 watter.


John, the 1200 watt rating is the microwave output power, not the power
required to produce it. My 1200 watt microwave draws just over 16 amps
to run. 120v x 16 amps = 1920 watts which is over the continuous
output rating of the Honda (1600 watts). It means the Honda has to run
near or at it's "surge" capacity continuously in order to power the 1200
watt microwave.





I would figure most microwave units should be about 14 amps max. They are
designed to run on 15 amp circuits.

Max on a 15a circuit is 12a (1440w). There are a few exceptions but
none if it has a plug on it.



I am not a code expert but why then, when you go to Lowe's or Home Depot
are the wall receptacles marked as "15 amp" or "20 amp"?

I've always wired a 20 amp outlet with 12 ga romex and 15 amp with 14
ga. and use the appropriate breaker in the service panel. More often
than not I skip the 15 amp altogether and just wire for 20 amp.

Have the codes changed?

No.
A 20a has to be on 12ga but you can put a 15 on either as long as
there is more than one receptacle on the circuit. A duplex is 2.
There is no limit to how many you put on a circuit tho in residential.

Commercial has a 180va per duplex (90 per receptacle) rating for each
based on full circuit ampacity (not the 80%). I think Canada extends
that to residential.

The thinking in residential is receptacles are placed for convenience,
not actual load and most will not be used most of the time so you can
have all you want on a circuit. The NEC does not address "design".
Basically they are trying to avoid the need of extension cords and
cords running across doorways so the general rule is you are always
within 6' of a receptacle without crossing an opening. That includes
any wall space 24" or wider.
In the kitchen, on the counter top you are 2' from a receptacle.
This takes about 6-7 pages of fine print and pictures in the NEC to
describe. Damn lawyers ;-)
210.52 is one of the more confusing articles.



I understand all the convenience stuff but you said that "Max on a 15a
circuit is 12amps). So why do the 15 amp receptacles say "15 amps" on
them? Why is the 15 amp circuit fed from a 15 amp breaker? If code
says "max on a 15a circuit is 12 amps" why aren't the breakers 12 amps
and the receptacles labeled "12 amps" ?

That is per plug (or piece of fixed in place equipment)
There are a lot of things going on here. The rated amperes on a device
(receptacle switch etc) is what it can handle without burning up (per
the NRTL ; like U/L)
The ampacity of a conductor is what it an handle without burning up.
(and remain in a safe condition)
You dealt with labs, You know that stuff.
Then there is the code that tries to build an 80% safety margin into
everything. 15 becomes 12 and 20 becomes 16.
That is really only applicable to continuous loads (3 hours) but they
always err on the safe side. If you can plug it in, they assume you
need all help you can get so the NRTL puts the 1440w limit on a NEMA
5-15 plug and 1920w on a 5-20.





Ah, I think you are referring to industrial code requirements. Not sure
they all apply to residential wiring in a house but again, I am not
an electrician and don't even have a current code book. :-)

Nope 210.21(B)(2) applies to everyone
(2) Total Cord-and-Plug-Connected Load. Where connected
to a branch circuit supplying two or more receptacles
or outlets, a receptacle shall not supply a total cord and-
plug-connected load in excess of the maximum
specified in Table 210.21(B)(2)
http://gfretwell.com/electrical/Tabl...21%20B%202.jpg


The equipment I used to build had many three phase motors and other
relatively high powered components most of which ran on three phase
power. Most were 480v, delta and occasionally 208 wye, depending
on what the customer's service was. Typical service requirements
for the average system was 60-80 KVA

I used to spec the service requirements for the
whole system so the customer could plan for it' installation.

When I first started doing this and being knowledgeable of which motors,
etc. would be on and which would be off during the system's operation, I
specified the the service for the maximum KVA it could draw at any time
with a safety factor. The systems never had *all* the high power
consuming components running at the same time.

Later, as the company grew, more people were hired and my role became
more corporate management versus technical I hired an electrical
engineer with a P.E. to manage the electrical department. He changed
the way the systems were spec'd to include *all* the motors, etc. even
though they would never run together at the same time. He said the way
I had been doing it was ok ... safe ... but the code required the total
of all, running or not. All it did was cause the customer's service
requirements to go up dramatically but needlessly.

If the motors are not electrically interlocked so they can't run
together you need to compute the load based on the largest one at 125%
and the rest at 100% of the full load amps

430.24 Several Motors or a Motor(s) and Other
Load(s). Conductors supplying several motors, or a motor(
s) and other load(s), shall have an ampacity not less
than the sum of each of the following:
(1) 125 percent of the full-load current rating of the highest
rated motor, as determined by 430.6(A)
(2) Sum of the full-load current ratings of all the other
motors in the group, as determined by 430.6(A)
(3) 100 percent of the noncontinuous non-motor load
(4) 125 percent of the continuous non-motor load.
Informational Note: See Informative Annex D, Example
No. D8.
Exception No.1: Where one or more of the motors of the
group are used for short-time, intermittent, periodic, or
varying duty, the ampere rating of such ~motors to be used
in the summation shall be determined in accordance with
430. 22(E). For the highest rated motor, the greater of either
the ampere rating from 430.22(E) or the largest continuous
duty motor full-load current multiplied by 1.25
shall be used in the summation.
Exception No.2: The ampacity of conductors supplying
motor-operated fixed electric space-heating equipment
shall comply with 424.3(B).
Exception No.3: Where the circuitry is interlocked so as
to prevent simultaneous operation of selected motors or
other loads, the conductor ampacity shall be permitted to
be based on the summation of the currents of the motors
and other loads to be operated simultaneously that results
in the highest total current.