Genset voltage reg: capacitor vs. AVR

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

"You don't even need the motor/'pressor mounted on a tank, per se."

For some reason I never thought about doing that. Thanks for bringing
it up! Being able to move this setup around easily is going to be a
factor. Also, this would allow me to go with a vertical tanks.

On 2/17/2013 9:43 AM, Existential Angst wrote:
> > wrote in message
> ...
> On Feb 17, 9:57 am, Robert > wrote:
>> On Feb 17, 8:49 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. An AVR sharpens this up.
>>
>>> I don't quite understand how this works, and part of the intent of Q was
>>> to
>>> shed some light on this.
>>
>>> 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
>>
>>>> Pete Stanaitis
>>>> ----------------
>>
>> I thought that it was a possibly that you had heard
>> of a "capacitor regulator' that I haven't, after 35
>> years as an electronics design engineer. So I
>> googled the subject and was unable to come up
>> with a single circuit/instance where a capacitive
>> system was used as a regulator....
>>
>> I have the background to comment on the subject,
>> so if you will provide a website that comments
>> on how a capacitor or "capacitive circuit" can
>> regulate the output of a genset, I will study it
>> and give you an opinion, which, obviously you can
>> accept or reject....
>>
>> I don't post this to insult you, but I really don't
>> see what you are asking ..- Hide quoted text -
>>
>> - Show quoted text -
>
> It's not hard to find discussion of caps as voltage
> regulators. Here's an example, about a third of the
> way down in this thread:
>
> http://www.smokstak.com/forum/showthread.php?t=16338
>
> Seems like a pretty crappy thing to find though on a
> $3000 generator.
> ==================================================
>
> Inneresting thread. But I think one can conclude that caps are not
> regulating, they are tuning, balancing. with mebbe an itty bitty bit of
> regulation as a perk to tuning.
>
> But if you follow the op Jim McIntyre, what his cap(s) did was raise/lower
> the voltage. The unit itself, apparently pretty high quality, seems to have
> had inherently good regulation between the generator itself and the motor.
> Anthony W. commented that
>
> "It sounds as if Kubota did their homework on the winding ratios in your
> set. As you found, the cap value isn't too critical in a "good" set within a
> reasonable range. Problems usually only show up when a certain critical cap
> value is exceeded.
> Also in the case of a non-linear load such as a switching power supply,(if
> you run your computer off of one) plug an incandesent lamp or two in as
> well. I don't know that it would hurt anything, but the waveform looks
> "slanted" on a 'scope when only a switching-type load is applied.
> The only troubles I have had with the several old Cap regulated sets I have
> owned are bearing issues and the cap going "open". "
>
> And the quality of the linkage between the generator/engine was proly
> superior.
>
> Notice, tho, that when McIntyre increased his cap size, the voltage
> regulation went from about 1% to 2%.
> Note that in mine, a much larger unit, the regulation, from midpoint, is 4%
> right now -- not terrible terrible, but again, not 1%.
>

I don't think it would be too far out in space to think of the capacitor
regulated generator as being related to a ferroresonant transformer or a
CVT, Constant Voltage Transformer. The only difference
is there is a mechanically rotating winding. ^_^

TDD

The Daring Dufas wrote:
>
> I don't think it would be too far out in space to think of the capacitor
> regulated generator as being related to a ferroresonant transformer or a
> CVT, Constant Voltage Transformer. The only difference
> is there is a mechanically rotating winding. ^_^


A CVT requres a sepereate winding to resonate with the cap. If it
were part of an active circuit, the Q would be too low to do any good.

On 2/17/2013 12:04 PM, Michael A. Terrell wrote:
>
> The Daring Dufas wrote:
>>
>> I don't think it would be too far out in space to think of the capacitor
>> regulated generator as being related to a ferroresonant transformer or a
>> CVT, Constant Voltage Transformer. The only difference
>> is there is a mechanically rotating winding. ^_^
>
>
> A CVT requres a sepereate winding to resonate with the cap. If it
> were part of an active circuit, the Q would be too low to do any good.
>

I did write "related". ^_^

TDD

On Feb 17, 9:32*am, " >
wrote:
> On Feb 16, 8:17*pm, "Pete S" > wrote:
>
> > 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.
> > What kind, model and serial number *of genset do you have that currently has
> > no voltage regulation built in to it?
>
> > Pete Stanaitis
> > ----------------
>
> I think he's saying he has a cheap generator that uses
> a cap for voltage regulation. *They apparently do that by using
> a cap in conjuction with the power source for excitation.
>
> But a better question might be
> why would someone living in NYC, who has a critical need
> to run CNC eqpt during a major power outage, be concerned
> about spending $400 for decent voltage regulation? *You think
> that would have been in the decision for the generator from
> the start.

Many of the transformers and other circuitry in lower manhattan are
still being put back up. Most of that stuff was underwater (salt
water) south of 32nd street. I wonder if he's reparing generators.
I'd repair the diesel ones. There'd be more money in those, but stick
to repair manuals and their one eight hundred tech numbers.

On Feb 17, 10:09*am, (Scott Dorsey) wrote:
> > wrote:
>
> >I think he's saying he has a cheap generator that uses
>> a cap for voltage regulation. They apparently do that by using
> > a cap in conjuction with the power source for excitation.
>
> I'm not sure how that works.

You mean whether the cap is shunted to the load and power source?
Because "in conjunction" means "in series with" right? At least,
that's how I've heard it mentioned before.

On Sat, 16 Feb 2013 10:13:55 -0500, Existential Angst wrote:

> What are the pro's/cons of each?
>
> One pro for caps is that they are cheaper! The AVR ditty for my unit
> would cost another near-$400.
> The pro for AVR is, presumably, much tighter voltage regulation with
> load.
>
> But mebbe AVR has its limits ito ruggedness?
>
> The voltage swing on my genset is 250 - 230 V, 0-50 A. Units with AVR
> claim 1-2% regulation.
>
> Should I spring for the AVR? If a major outtage occurs, I'll be running
> cnc equpment from it.

Do you have a link to a site that sells the AVR ditty? If it's
regulating the field current of the generator in response to the
generator voltage, and if all the genset does is rely on the motor's
governor for speed regulation, then it should give better regulation.

But I can only speak from a combination of a deep knowledge of control
systems theory, a reasonably deep knowledge of how generators work and
how Briggs and Stratton engines work, and a near total ignorance of how
people actually put these things together in practice.

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

On Feb 17, 9:24 am, " >
wrote:

>
> It's not hard to find discussion of caps as voltage
> regulators. Here's an example, about a third of the
> way down in this thread:
>
> http://www.smokstak.com/forum/showthread.php?t=16338
>
> Seems like a pretty crappy thing to find though on a
> $3000 generator.

Thanks for the link. From that thread, I determined that the
keyphrase I needed to google was "alternator feedback
capacitor".... That gave me the link to a paper called
"Field Initiation Design Fundamentals for Pulsed Alternators"
which has an abstract giving a short explanation of how
the capacitor works. This was an IEEE paper.

It is simply a bootstrap giving feedback to the field of
an alternator....... Not a particularly good regulator, but
sufficient for non precise applications. I had never seen
this before, as I had only used electronic regulators to
the field windings of an alternator with a DC field and not pulsed
alternators.... Live and learn.....

Anyway, if the voltage regulation is critical , an
electronic regulator would work far better.

"Robert" > wrote in message
news:11864198-e5a3-4016-b3dc->
> Anyway, if the voltage regulation is critical , an
> electronic regulator would work far better.

Would it be better to regulate the peak, average or RMS voltage if the
load draws non-sinusoidal current?

I became concerned with the peak after a poorly regulated generator
burned out the transient voltage suppressors in an outlet strip, in a
cloud of purple smoke.
jsw

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