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Bill[_12_] Bill[_12_] is offline
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First recorded activity by BoatBanter: Jan 2017
Posts: 4,553
Default Betsy displays some sense!

wrote:
On Fri, 12 Oct 2018 18:59:22 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 3:45 PM, wrote:
On Fri, 12 Oct 2018 14:50:19 -0400, "Mr. Luddite"
wrote:

On 10/12/2018 1:22 PM,
wrote:
On Fri, 12 Oct 2018 09:24:03 -0400, "Mr. Luddite"
wrote:


I need to correct some readings. The current draw of 16 amps was when
I was running the 1200 watt microwave on the generator. I realized it
may have been a higher current reading due to shape factor of the
AC waveform generated by the generator andif there was any voltage droop
due to the generator being loaded close to it's max. So, I just
measured the current it draws when powered by commercial power.

Voltage is 121 vac. Current draw is 14 amps. So, it's using 121v * 14
amperes to produce 1200 watts of microwave power output or 1694 watts
"in" to produce 1200 watts "out".

Very reasonable and believable readings to me.

Not sure about a Honda inverter but my Briggs did not have that ugly a
wave form at pretty much full load
http://gfretwell.com/Propaneproject/Waveform.jpg




I don't know the details of an inverter generator design but from what I
understand they are not dissimilar to a DC to AC inverter or switching
power supplies. Initially the output is a modified square wave but is
then smoothed into a decent sine wave. Honda and other manufacturers of
inverter generators make a big deal about this. There is no big
generator coil in an inverter.

No scope?


Nope. Lent it to a guy and never saw it again. Nice one too.
Tektronix 2445B dual trace that I bought on eBay for cheap bucks.
It worked fine.

If you search around Honda and some other inverter generator
manufacturers have posted images of the waveform for their generators.
Look pretty good.


I gave that scope in the picture to Wayne. I am sorry I didn't pluck a
few more out of the dumpster when IBM was throwing them away.
(Harvey Johnson the daddy of the AFCI and my dutch buddy got one too)
The 453 is a nice portable with fairly respectable credentials. I had
one in my car for almost 3 decades and I can make it dance ;-)
I have his big brother the 465 on my electronics bench. (little better
bandwidth and a whole lot better display)
http://gfretwell.com/electrical/CFL%...0a%20scope.jpg

BTW, that is a current transformer hanging on an AC load
That was part of a little science project I did on CT transformers.
How I will be measuring current on my generator with junk meters
http://gfretwell.com/electrical/CT%20fun/
"Stay thirsty for knowledge my friend" -A bearded American


I loaned my really nice portable Tektronix field service scope to a buddy
who was doing contracting about 20 years ago. Needed it a while back, but
do not know if still works. He passed away 3 months ago, so may ask his
wife it is still around.