3000W Chinese Gensets Info.

[professor95]

professor95 wrote:
EDIT ADDED 45/5/2013- When this thread started in March of 2005, I never expected to see it survive this long or amass the quantity of information that has been shared here.

In the eight year run of this thread we have amassed almost 10,000 postings and surpassed a million views. This creates somewhat of a dilemma for anyone who has just discovered the forum.

Since the amount of information is virtually overwhelming, I suggest you set your preferences for this thread to read "newest first" and then begin to page backwards.

What you will find in these pages is a wealth of info on virtually any make or model of Chinese manufactured synchronous (non-inverter) generator in the 3,000 watt performance class. Info will include how to rewire series coils to parallel to obtain maximum wattage from a single 120 volt outlet. Tips on further reducing sound levels, how to care for these generators, which ones are "RV ready" and provide the best overall performance for the dollar invested. Which companies NOT to deal with, where the best prices are, how to safely wire the generator into a home or RV, how to check your RV for electrical faults, sources for generator accessories, which 20/30 adapters are safe to use and which are not. How to convert a gasoline generator to propane or NG. This is only the beginning. The forum has a life of its own with the focus sub-topic switching frequently. Still, the main topic of utilizing the amazing, inexpensive Chinese gensets is always there. The amount of creativity and innovation presented in these pages is indicative of the talents shared in the diverse backgrounds of the folks who make up our combined RV community.

Many of the original brands and models of Chinese gensets mentioned in the introduction and early pages of the thread have since disappeared. New EPA and CARB emissions requirements, company bonds assuring the emissions warranty will be honored even if the company goes out of business, and fierce competition in the industry have changed the playing field. Champion Power Equipment has become the apparent "trophy team" providing an ever expanding retail outlet, an ample parts supply, a strong warranty and excellent customer service. CPE has continued to improve their product and now offers a new model (#46538) with exclusive convenience, safety and performance features aimed at the RV market. Big names like Cummins/Onan, Honda and Generac all now have Chinese built open frame synchronous gensets available. Ironically, the prices often found on these gensets has not significantly changed during the past eight years - even with the devaluation of the American Dollar and new EPA/CARB requirements.

I also encourage you to use the search function and even the advanced search options to find information. Key works such as "rewiring", "PowerPro", "Champion", "Onan Homesite", "Duropower", "ETQ", "Jiung Dong or JD", "Tractor Supply", "Costco", "Lowe's" and "Home Depot" are all examples of keywords that will give you specific information on different models being sold by retailers today.

Or, you can fill your glass with your favorite beverage (keep more close by - maybe some munchies as well :D, sit back at your computer, tell your wife (or significant other) that you will see her in the morning and spend the next 10 or so hours reading through the postings.

No one on the forum gets mad if you ask a question that is a repeat. Please do not hesitate to post to the forum. All questions are considered important and those active on the forum will do their best to respond with a valid answer.

Also note we are not out to knock the Honda, Yamaha, Kipor or other brands of high end digital gensets. We recognize the quality of these products and their suitability for quite, efficient RV use. But, there is a flood of reliable, inexpensive and comparatively lower cost gensets coming out of China that are excellent alternative choices for the RVer wanting power to run an air conditioner, microwave, etc. without excessive noise or breaking the budget.

Oh, one last thing. The folks on this forum are true gentlemen. We do not flame one another or the product discussed - period. Ugly contributors usually have their comments and remarks ignored by our masses. It is not a forum to start arguments to obtain a clear win. We do disagree on many issues, but we have all agreed to do that in a respectable manner.

We now have the introduction of more and more inverter gensets. There is a rather extensive thread named "The Official Unofficial Champion 2000i Generator" on this forum. Today, I added info on the new Champion 3100i inverter genset. Discussion on this product may get moved to its own thread at a later date.

Many have looked upon this thread with distain saying Chinese is cheap and doomed to failure. I remember saying exactly the same thing about Japanese products a few decades back. But, over the past eight years the track record for Chinese built generators has shown otherwise.

Please, join us in a fascinating journey down the Chinese built genset road of knowledge.

This is the question I posted that got it all started back in March 2005.......

Randy

For a little over a month now, I have been somewhat intrigued by the availability of a 3000 watt, 6.5 HP generator at Pep Boys and Northern Tool for under $300.00. The engine on this generator looks identical to a Honda 6.5 HP OHV engine. Knowing that the Chinese have become very adept at “cloning” reputable technologies from other manufacturers, I was not surprised at the similarities. Neither store could give me any information on the generator nor did they have a “running” display model.

I have done a little research. This is what I have discovered:

Many of these generators are imported by ELIM International (www.eliminternational.com) out of Buffalo, New York from Jiung Manufacturing in China. (The unit at Northern is identical but carries the JIUNG name.)

The engines are indeed a Chinese knockoff of the popular 6.5 HP 196cc Honda Engine. “Supposedly” Honda has licensed the engine technology to the Chinese manufacturer of the product.

The Chinese company that makes the ELM3000 generators is a rather large, diverse, long-standing company with a reputation for “above average quality” Chinese made products (Jiung Manufacturing). There are many more Chinese companies making almost identical gensets.

The generators at PepBoys do have a six month limited warranty. But, it is only on the engine (not the generator) and requires paying for shipping to and from Buffalo. Probably not a very practical thing to do if you have warranty issues.

ELIM does supply replacement parts (a PDF parts manual is available on the ELIM web site). No prices are given for replacement parts nor is there an “availability listing”.

The generator head itself is a brushless design. The only really significant wear parts in the generator are the bearings – most likely universally available.

The published dB rating is 67 at 23 feet. This is “reasonably” quite for a generator of this size as most comparabl.... The 67 dB rating is the same as Honda gives their 3000 watt CycloInverter with a “look alike” eng...

[professor95]

daytona7 wrote:
Looks interesting but there are a few questions in my mind. Dual exhaust for the muffler and exhaust pipe?, but the inside heat would still be maintained as there is nothing to draw the heat out and no way for fresh air transfers over the AVR and starter. The open bottom would still redirect/bounce the sound waves down then out.:h
I'm thinking(ouch another headache) that with the gas tank on top, there might not be a need for a top covering and just small openings around the corners of the tank to allow the sound waves to escape without causing a vibration of the tank and gas.
Now I need some Ice Cream to take care of my headache.

I guess you are writing about the GenTent design? Not sure about the reference to dual exhaust for the muffler and exhaust pipe - you are going to have to give me some glue to connect that topic as I am :h

My reference to the cardboard box and/or GenTent was more about sound reduction than the problems with air flow needed for cooling. I have previously stressed how air must flow and pointed out that sound abatement and cooling do not always complement each other. The compromise must be on sound reduction - not air flow. A fried AVR or melted engine is of no use to any of us. 🙂 Small enclosures work well for sound reduction but any irregularity in air flow will cause an extremely rapid temperature rise in the engine.:(

The cardboard box experiment was only to prove that significant sound abatement can be accomplished with common materials - to go further takes a lot more in the way of fine tuning and analyzing the frequencies we need to abate.

You have apparently developed an understanding of many the factors and problems that one can encounter while designing a working enclosure. Yes, they can lead to extreme headaches. I've found that butter pecan ice cream does a better job than plain vanilla.:C

[Trimsters]

daytona7
What you are describing is a Hermholtz Acoustic Trap/Resonator. It's a very effective sound trap that is tuned to specific frequencies. There's lots of reading to be done on this concept on the web. A classic example of this is blowing across the mouth of a glass softdrink bottle. That tone it makes happens to be the freq. it will trap. Stack a grundle of those on a wall in a room and those bottle will take that freq. out of the room. Phone booths in airports (remember those?) had stainless metal with holes in it, backed by dense fiberglass isolation. Only 1" thick, they would absorb the freq. that were common in large spaces but not the voice range.
Soooo, what you need is to do a spectrum analysis of the generator IN it's environment. You're going to see a spike in a the overall spectrum. That's what you want to kill/absorb. You can't do much about low freqs. They are to long a wave to deal with in the confines of an RV. But you can mount the generator on iso-mounts and keep lots of that low freq. from transmitting to the frame of the RV, making the RV a speaker...essentially. I've long since lost my files and spread sheets on hole dia vs. hole spacing vs. depth of absorber space = target freq. range. But you can find that info./formula on the web and make a quick spread sheet to plug in numbers.
Off the top of my head... standard Peg board with 1/4" holes + 1" HVAC duct board will just about nail the bulk of the nasties put off by our generators.
It might seem counter intuitive, but put the hard side of the peg board out (facing the noise source). Use a good construction adheasive to bond the rough side of the board to the fiberglass side of the duct board. (FYI, you can buy damaged or seconds HVAC duct board cheaper. Look to your local HVAC contractor as a source.) Do not plug the holes with smooshed adhesive. IF you build it to fairly close tolerances, corners all match up squarely, you can use metalized HVAC duct tape to hold it all together. DON'T use Duct tape... it has to be the metal tape... about 4" wide.
I'm not sure heat paint will do much for you in protecting the peg board. It will make it more weather resistant which is a big plus. I would paint it with Hammerite paint. That stuff is really tuff and very weather resistant.
Just my 2 shilling worth. I use this construction method and materials all the time in acoustic sensitive room designs.... only there we cover the face of the absorber with fabric.

Oh, another cool thing about the 'sandwitch' construction... you can put it on the table saw or use a skill saw and cut a door in it. Just add 1x1" wood pieces where the hing screws in. If you can taper the door cut, the better it will work at keeping sound from escaping from the cut-out area.

[toprudder]

professor95 wrote:
I once noted on this thread, "It is not so important to have the quietest generator in the campground, but to NOT have the loudest".

That is like the old saying "I don't have to out-run the bear, I just have to out-run YOU". 🙂

[daytona7]

Looks interesting but there are a few questions in my mind. Dual exhaust for the muffler and exhaust pipe?, but the inside heat would still be maintained as there is nothing to draw the heat out and no way for fresh air transfers over the AVR and starter. The open bottom would still redirect/bounce the sound waves down then out.:h
I'm thinking(ouch another headache) that with the gas tank on top, there might not be a need for a top covering and just small openings around the corners of the tank to allow the sound waves to escape without causing a vibration of the tank and gas.
Now I need some Ice Cream to take care of my headache.

[professor95]

daytona7 wrote:
I've been having a headache weekend.

All of your ideas are worthy of experimentation. Innovation is indeed the brother of invention and I have always appreciated thinking that breaks existing paradigms and steps out of the box. You appear to be on the right track for a new discovery.

One word of caution that you must keep in mind - A simple cardboard box will attenuate sound significantly - which is why SuperGen Products has been successful with their GenTent . Additional materials(s) may further reduce the transmission of annoying sound, but not necessarily at a level of significance that makes much difference to the human ear - or the camper sitting outside next door. I once noted on this thread, "It is not so important to have the quietest generator in the campground, but to NOT have the loudest".

Please let the thread know how your design progresses.

[daytona7]

I've been having a headache weekend.
Sound waves do not really bend around corners or curves, am I correct?
Your Pink insulation sound shield in reality just bounces the sound waves back and forth since the surface is too smooth to distort the sound waves, possibly causing a vibration?
Using an Acoustical panel with multiple holes, nocks and crannies absorbs more of the sound waves?
How would the use of:
1---1/8" thick panelboard, the type with holes used for hanger hooks, painted with Boron for fire proofing on the engine side
2---1/2" to 1" acoustic foam board with a 1/8" to 1/4" thick or same as #1 with raised foam cut in different sizes and shapes to distort the sound waves, attached but with no holes lining up between # 1 & 2
3---1" thick outer panel.
Total thickness about 2 1/2" on the sides and ends. The top should be the least worry.
An opening for the installation of a heat exhaust fan and cooling fans would still be used.
OR use of Silent Panel which is fire proof but possibly expensive.

[daytona7]

Professor, I hope you know that this thinking is giving me a headache by moving the cobwebs. Some time ago I remember a Liquid cooling system for computers and was "thinking"(there's that headache word again)if such a system could be applied to cooling an enclosed generator along with an exhaust fan to move the cooler air around or possible slots in the top of the enclosure for the heat to escape.
I gotta take a headache break. You do know that this could be a good project for your students.

[professor95]

daytona7 wrote:
Just a little something for your mind. How would a Hearth Rug be if cemented or attached to the inside walls of the Pink Fiberfoam generator box. They are fire resistent, light weight and fairly cheap, $35 and up.:@

Well, IMHO I would not say it is needed - but it shows that you are doing some great brainstorming! Still, if you are willing to spend the extra money, it might provide some benefit and give designers yet another material to consider.

Looking back through my WORD document files I ran across a couple of articles that I honestly do not remember if I posted or not. You know, I forget a lot of things :S.

Anyway, at risk of repeating, you have two primary objectives that can be in conflict with each other. One is the maximum possible reduction is noise level, the other is to maximize air flow for cooling (heat extraction). A single design that does only one or the other is easy - a design that does both gets more complicated.

On the subject of sound abatement, the article quoted below might be beneficial when considering what materials to use and what type of sound we are trying to cancel.

excerpted from Mix, August 1997, “Room Acoustics wrote:

All materials have some sound absorbing properties. Incident sound energy which is not absorbed must be reflected, transmitted or dissipated. A material’s sound absorbing properties can be described as a sound absorption coefficient in a particular frequency range. The coefficient can be viewed as a percentage of sound being absorbed, where 1.00 is complete absorption (100%) and 0.01 is minimal (1%).
Incident sound striking a room surface yields sound energy comprising reflected sound, absorbed sound and transmitted sound. Most good sound reflectors prevent sound transmission by forming a solid, impervious barrier. Conversely, most good sound absorbers readily transmit sound. Sound reflectors tend to be impervious and massive, while sound absorbers are generally porous, lightweight material. It is for this reason that sound transmitted between rooms is little affected by adding sound absorption to the wall surface.
There are three basic categories of sound absorbers: porous materials commonly formed of matted or spun fibers; panel (membrane) absorbers having an impervious surface mounted over an airspace; and resonators created by holes or slots connected to an enclosed volume of trapped air. The absorptivity of each type of sound absorber is dramatically (in some cases) influenced by the mounting method employed.
1) Porous absorbers: Common porous absorbers include carpet, draperies, spray-applied cellulose, aerated plaster, fibrous mineral wool and glass fiber, open-cell foam, and felted or cast porous ceiling tile. Generally, all of these materials allow air to flow into a cellular structure where sound energy is converted to heat. Porous absorbers are the most commonly used sound absorbing materials. Thickness plays an important role in sound absorption by porous materials. Fabric applied directly to a hard, massive substrate such as plaster or gypsum board does not make an efficient sound absorber due to the very thin layer of fiber. Thicker materials generally provide more bass sound absorption or damping.
2) Panel Absorbers: Typically, panel absorbers are non-rigid, non-porous materials which are placed over an airspace that vibrates in a flexural mode in response to sound pressure exerted by adjacent air molecules. Common panel (membrane) absorbers include thin wood paneling over framing, lightweight impervious ceilings and floors, glazing and other large surfaces capable of resonating in response to sound. Panel absorbers are usually most efficient at absorbing low frequencies. This fact has been learned repeatedly on orchestra platforms where thin wood paneling traps most of the bass sound, robbing the room of “warmth.”
3) Resonators: Resonators typically act to absorb sound in a narrow frequency range. Resonators include some perforated materials and materials that have openings (holes and slots). The classic example of a resonator is the Helmholtz resonator, which has the shape of a bottle. The resonant frequency is governed by the size of the opening, the length of the neck and the volume of air trapped in the chamber. Typically, perforated materials only absorb the mid-frequency range unless special care is taken in designing the facing to be as acoustically transparent as possible. Slots usually have a similar acoustic response. Long narrow slots can be used to absorb low frequencies. For this reason, long narrow air distribution slots in rooms for acoustic music production should be viewed with suspicion since the slots may absorb valuable low-frequency energy.

OK - let me add to the above a piece of an article I wrote in 2006 that was, in part, drawn from the sound abatement research I had conducted.

Professor95 wrote:
I began to conduct some much needed research on the characteristics of sound waves along with their propagation and reproduction. Not surprisingly, the best source of information was found from elements of acoustical design. Buildings, auditoriums, speaker cabinets and even boom cars all draw from the same basic principles.

In designing a new enclosure, there were four basic principles that had to be considered; reflection, absorption, frequency and amplitude.

Through measurements made with a microphone, graphic equalizer and oscilloscope it was determined that the majority of sound energy was, as expected, under 5,000 Hz.

The amplitude had previously been established through measurements with a digital sound level meter and manufacturer’s data.

Since the sound frequencies were below 5,000 Hz, a small enclosure would do a better job of canceling the sound waves. Low frequencies have a longer wave length or period than high frequencies - the smaller the cabinet, the more attenuation of low frequency sound will occur. Audiophiles depend upon large diameter speakers, cabinets and tuned reflex ports for low frequency reproduction. Conversely, small diameter speakers and cabinets do a better job of reproducing high frequencies.

Anyone who has ever hooked up a set of speakers knows that they must be equally phased to reproduce sound properly. If one speaker is out of phase, or pulling the speaker cone in while the opposite speaker is pushing the cone out, the resultant sound waves will somewhat counter each other. Reflection of sound waves would be important in an enclosure to reduce sound pressure.

Absorption of sound waves turned out to be a considerably more complex than I originally believed. While it is true that materials with an open cellular structure can do an effective job of absorbing sound, caution must be exercised in selecting the material to assure there is sufficient density to cancel the effects of sound transmissions. Simply stated, when sound waves hit the surface of some materials the molecules in the material can also move or vibrate at the same rate as the sound pressure pushing against the material. Density, or thickness, of the material is a factor for consideration.

All of the experiments I considered were never completed. I had to choose one or two and run with the ball. The 2" foam board was available and met in part the sound reduction goals I sought while being lightweight and inexpensive. But, I emphasize that there are other materials that may be much better and more available. Considering the above may be beneficial in selecting a material. Additionally, it is not only the material but the path of the sound waves - which, by the way, are in the 5,000Hz range and DO NOT like to go around bends or corners. But, alas, turbulence can be introduced for cooling air flow by this type of design - so we go back to compromise 101 - which is where I left off......

[daytona7]

Just a little something for your mind. How would a Hearth Rug be if cemented or attached to the inside walls of the Pink Fiberfoam generator box. They are fire resistent, light weight and fairly cheap, $35 and up.:@

[professor95]

daytona7 wrote:
Professor,
I think you better go back to teaching. Retirement is giving you too much free time to try new sound abatement projects and your possibly driving your wife crazy. What happened to your below $200 and the same weight as the original generator project which now is probably in excess of $300 and pounds?:h

Well, funny you should ask. It went like this -

Bought:
a sheet metal brake, shear and roll press at Harbor Freight - $400
a 4' x 6' sheet of diamond plate 16 gauge aluminum - $185
a regulator, tank and gas for my MIG welder to weld aluminum $160
a roll of flux core .035 aluminum welding wire $30
4 sheets of Dynamat sound absorbing material $130
1 used RV Fan-tastic fan from a friend $50
1 Woodard/Garretson low pressure LPG regulator $85
Assorted hoses, clamps, fittings, etc. for LPG conversion $60
Stainless steel exhaust flex coupler $30 - now being used on
the Cat-5 Chinese Champ in the basement of the Volvo to
route exhaust to the back of the truck cab. It runs the
A/C in the truck when we park to shop or eat so the dog
stays cool.

Needless to say, I kinda' blew the budget for the project.

The originally planned project is still un-built and parts sitting. I do occasionally use the MIG welder and sheet metal brake & shear. I am waiting for a round-tuit day to complete the project as originally planned.

In the interim, I bought two CPE 2000i inverter generators with the parallel kit ($1,100) thinking I would use them when dry camped in a "noise sensitive" environment. I discovered that the 40008 Champ in the basement of the fiver with cooling fan and outside muffler was actually quieter than the inverter twins under A/C load. Go figure :h Inverters are nice for small loads when I can keep the engine speed down. Especially nice for battery recharging and low fuel consumption. I carry at least one 2000i in the drom box on the truck.

I can't drive the wife crazy - she is too tolerant and goes along with my projects "as long as they make me happy". You gotta understand that this is the DW that simply said "OK" when I told her I wanted to buy a used semi and convert it into a motorhome to pull our fifth wheel. But, she did balk a bit when I suggested building a small submarine out of a like-new 300 gallon propane tank. That project is also on hold 😉

I never quit teaching - I just don't get paid anymore.

[daytona7]

Professor,
I think you better go back to teaching. Retirement is giving you too much free time to try new sound abatement projects and your possibly driving your wife crazy. What happened to your below $200 and the same weight as the original generator project which now is probably in excess of $300 and pounds?:h

[professor95]

daytona7 wrote:
Professor, I'm lucky to live in an area with several PIY junk yards nearby with a few burned out RV's and to top it off, a few neighbors who are RV Master Tech's and one Industrial Electrician along with a former neighbor who works for his father's HVAC company. Between us, we might be able to bang heads hard enough to figure something out. Hardest part is findeing the Owens/Corning 2" Pink rigid insulation.
Again, A Million Thanks!

The 2" pink insulation board was overkill. Today I would build the enclosure you referenced using 1/2" thick James Hardy Concrete Backer board. Why? Well, you can cut it with a saw or knife (score), it is fire proof, water proof, rot proof, can be painted and it's high density makes an excellent sound abatement material. Use some aluminum angle to fasten the corners together.

Two more photos.... This is the very first sound abatement enclosure I ever made. I Isolated the carb intake and fan behind the recoil starter from the inside of the box. Same for the AVR end. It worked pretty good, but the exhaust fan was too small so I abandoned the box and built #2.

[daytona7]

Professor, I'm lucky to live in an area with several PIY junk yards nearby with a few burned out RV's and to top it off, a few neighbors who are RV Master Tech's and one Industrial Electrician along with a former neighbor who works for his father's HVAC company. Between us, we might be able to bang heads hard enough to figure something out. Hardest part is findeing the Owens/Corning 2" Pink rigid insulation.
Again, A Million Thanks!

[professor95]

daytona7 wrote:
Professor, Thanks for the pictures! Remember, a picture is worth a thousand words. In my case they are worth checking 975 postings to find what is needed. I'm very sure your latest posting will be very useful to other (lazy like myself) new commers.:o

Leon,
Just to add some additional information that might be helpful. The fan I am using is one of two I found in a U-Pick-It auto salvage yard. I "think" the fan came off a Honda's radiator, but I honestly can't remember since I have scrounged way too many parts off wrecked cars. The blade is 12" and the fan frame 14". A RV "Fan-tastic" vent fan would most likely work well too - but at a high price retail.

Anyway, if you look closely at the photo below you will see a small power cord coming out of the 120VAC duplex outlet on the generator and disappearing into the fan box. Inside the fan box is a relay with a 120VAC coil that automatically switches on 12VDC power for the fan when the generator starts. The 12VDC power for the fan is drawn from the RV batteries. With a 9.5 amp draw from the fan a typical fully charged group 24 RV battery can run the fan for at least eight hours before the voltage begins to drop enough to effect fan speed. At some point a battery charger will need to be employed if the generator is used for an extended period of time.

Any fan, 12VDC or 120VAC, powered from the generator will eventually reduce the wattage available for other appliances - like an air conditioner. I have found that the 12VDC fans are easier to find, cost less and ultimately have the right size blades and motor to do an excellent job of exhausting hot air. Unfortunately, the issue of powering a 12VDC fan is slightly more complicated since the generator cannot directly supply the needed 12VDC and amperage required.

One more issue to consider..... if the air intake for the carburetor is inside an enclosure that uses an exhaust fan it is possible for the air inside the box to have a negative static pressure. This occurs when the air intake opening is too small for the CFM of the exhaust fan. With the negative static pressure the carburetor does not function properly and engine performance drops. In these cases it is a good idea to modify the air cleaner so outside air is used.

Have fun with your project.

[daytona7]

Professor, Thanks for the pictures! Remember, a picture is worth a thousand words. In my case they are worth checking 975 postings to find what is needed. I'm very sure your latest posting will be very useful to other (lazy like myself) new commers.:o