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jon_banquer[_2_]

On Feb 17, 9:50*pm, jon_banquer wrote:
On Feb 17, 9:40*am, "Existential Angst" wrote:

"jon_banquer" wrote in message

...
On Feb 17, 8:23 am, "Existential Angst" wrote:

wrote in message

....
On Feb 17, 9:49 am, "Existential Angst" wrote:

"Pete S" wrote in message

...

I don't understand your question.
If you mean "capacitors" when you say "caps", I don't know how they
would
deal with output voltage regulation in any meaningful way.

Ditto. ergo my Q. I guess they must in some fashion, just like you
balance
rpc's with caps.

What kind, model and serial number of genset do you have that
currently
has no voltage regulation built in to it?

http://www.generatorsales.com/order/...Generator.asp?...
modified for tri-fuel.

It is regulated, just not to 1 or 2%, a swing of 230 to 250 V, from 50+
amps
down to zero amps.
If you at mid-load it's 240 V, that's +/-10V, which is not terrible, but
it's not 1% either.

Assume no electrical-type regulation at all. There is something between
the
generator itself and the gas engine that ups fuel flow with load,
maintaining a semi-constant voltage.

That would be the mechanical engine governor.
================================================== ==

I sure would like to know the details on how those work.

An AVR sharpens this up.

Yes

I don't quite understand how this works, and part of the intent of Q was
to
shed some light on this.

See my other post to a discussion.

I also figgered that if the feedback between generator and engine was
good
enough, AVR wouldn't be needed.
So basically I"m curious about the design of these things.
--
EA

Do you realize what you got for $2800? They take a Honda
engine and bolt it on to some generator made by someone
else. Perhaps you can shed light on to who that someone
else is, but given that it uses a cap for voltage regulation,
I would not be surprised that it's a cheap Chinese one.
Then they take pretty pictures of the thing with Honda showing
all over in the pretty pics and a lot of people make the
assumption that they are buying a Honda generator.
I don't believe that is the case.
================================================== ===

McCaulte (sp?) makes the generator.

And yes, they mix'n'match.... but presumably they do it pretty well, altho
I got a li'l short-shrifted on the AVR deal....
I don't know that they are being misleading, as much as emphasizing the
Honda part.... LOL
Thin line, admittedly.

Further arousing suspicion is that they claim it's 15KW.
Then if you read the specs, it says it's rated at 13.5KW
continuous.
=============================================

This is typical. Generac does this.

Then they say it has a 50 amp main
breaker, which equates to 12KW, in my world.
======================================

Yeah, I noticed that. And they trip fast, too!
I may put in my own 50 A slower-tripping or even 60 A breakers.

You with me so far? Further arrousing suspicion, they
quote fuel consumption in gallons, ie it's based on running
the engine on gas. So, next, let's look at the spec for
a Honda GX690. It says it produces 22hp running gasoline.
I'm no expert in conversions from gasoline to nat gas, but
AFAIK, when you run a gasoline engine on nat gas, you
have about 15% less energy output. Maybe someone has
the exact number. That means you really have about an
18hp engine.
===============================================

Again, par for the course. I simply went for the most watts. Those watts
will be similarly de-rated in most scenarios, so I just went with the
biggest number.

I've looked into generators a bit and what it takes to
power them. I don't think you can get 15KW out of an
18hp engine. A Generac 12KW unit for example, uses
a 26hp engine.
================================================

Oh, but I did get very nearly the full 13.5 continuous (on gasoline), and
proly could have gotten sig. more. I'll have to jump/replace the breaker,
tho. Already at near-full load, it started a 26 gal compressor, w/ nary a
hiccup.

A 26 hp engine for 12 kW is suspect as well, from two povs:
First, I suspect Generac hp is like Sears hp.
Second, if it IS 26 hp, yer just sipping lots more gas.... which was one
of
the things I was going to discuss in my upcoming Generator Manifesto......
big-azz generators, in no-load conditions, are not economical.

I really couldn't find much better overall bang fer the buck, watt-wise.
The Honda motor is a plus, and the unit is VERY compact.
Generacs are big and complicated. OK, I spose, for the home-moaner who
justs likes to dial the telephone when sumpn goes wrong, and from what
I've
read about generac, they will be using their telephone fairly often.

Here's some of my take on this:

I would recommend the Sam's club 8,750 W blackmax, at $999, for most
people
with more than the basic needs. You can get it modified for tri-fuel, and
the link I provided sells a modified blackmax for $1600 -- about a
$200-$400
preimum over what you would pay if you did it yourself, but with a lot
less
headache, and somewhat of a guarantee. The blackmax also has AVR, iirc,
and
performed quite well, before it grew feet.

My unit does not come with a gas tank, but which is actually an advantage,
imo, because you just drop the genset's hose down any gas can (or your
car's
gas tank, if you can snake it in), and Wala, gasoline power.

I went for the 15 kW unit, in the second go-around, for many of the
reasons
you stated:
By the time you get done de-rating for whatever whatever reasons, you
have a lot less than when you started, so I figgered I'd just double the
size from the gitgo.

Really a lot of g-d work. The other bottom line to all this is that unless
you have a water-cooled 4 cylinder unit, you gotta simply build a separate
sound-proofed shed for these noise buckets.
A lot of my work so far went in to testing, given my cnc liabilities. So
far so good, but really a pita -- for sumpn I may NEVER use.
--
EA

Just some more things to think about.

It seems it's often impossible to buy the right package for what
someone wants.
============================================

Amazing how that works.... in almost everything! *From vitamins to cars to
cnc to real estate.....
Canada here I come.....

An example is an air compressor. I don't intend to run my air
compressor day in and day out so I don't have the need for a very
heavy duty dual stage air compressor pump like this one:

http://www.northerntool.com/shop/too...ct_42535_42535

I'd like this air compressor pump because it's got an 18 CFM rating at
90 PSI and it's got a decent price.

http://www.northerntool.com/shop/too...7235_200387235
================================================== ======

I'd be careful of Northern Tool. *They are not above shenannigans.
I'd look at the displacement of the pistons, and try to guestimate the rpm,
and match that to cfm claims of similar sized compressors. *Ahm no 'spert,
but 18 cfm at 90 psi seems pretty substantial. I'da thought more like 5 or 8
for that size.
I'd check out comparable sized Quincy's, or other reputable brands, and see
what they list.

The husky compressor is surprisingly civilized.

I'd like this motor:

http://www.northerntool.com/shop/too...6765_200306765

When I try an find a reasonably priced horizontal air tank I'm ****ed.
Prices are insane. Looks like my only choice will be to buy a used
horizontal air tank.
================================================== ==========

Well, mixing/matching is not a bad idea, and proly a really good one. *Tanks
are tanks, motors are motors, so really what you want are a nice (quiet)
'pressor head, and a good regulator, with separate set points for
cut-in/cut-out, which bigbox stuff doesn't have.

Also, recall from a previous discussion that a big tank will help compensate
for smaller compressor size, and that instead of one big tank, a bunch of
small ones are the same as one big one, and a lot more manageable. I have a
bunch connected together, each one separately valved. *You don't even need
the motor/'pressor mounted on a tank, per se.
I've even got some BBQ propane tanks I want to hook in, but goddamm, do they
make it difficult to remove dat stuff in the 3/4 neck. *Also, there's no
drain, altho they are small enough you could put the drain on top, and just
tilt it to drain it.
--
EA

I'm hearing almost all air compressor pumps are made in either China
or India. That includes Ingersoll Rand. Thinking that Northern Tool
may not be the way to go. Found this. Like the price and the specs:

http://www.eatoncompressor.com/catal...43/1320611.htm

http://wiki.answers.com/Q/Are_Ingers...ade_in_the_USA