110V fan for enclosed generator...

[theycallmemorris]

I just came across this site after having already done the same thing to an 20X8.5 enclosed car hauler, which I'll have to get to next and get a few pictures up. But for right now, I'm working on silencing a generator. I just bought a Champion 3500/4000 and want to enclose it like I did my last one, but I've got a little problem. On my previous one I built an aluminum diamond plate enclosure to it with a 12 inch DC fan from an ATV. But... This new generator has no DC outlet. Just AC. I haven't really come across any AC fan that I'd trust to the elements. The one I had before was an extra for my four wheeler, which spent thousands of miles being dunked completely under water and never missing a beat. So far my only option I can think of is to get a AC/DC 10A converter, but all of them that I find seem to be for computers, like the one attached to this laptop. I don't know how that would hold up in the heat and elements. And for anyone worrying about if the fan were to shut off and the generator overheat, I am aware of that risk. The previous generator is still going strong with the set-up, I just gave it to my dad when I moved out of state.

Any suggestions or ideas?

[RvMan56]

I would get this http://cgi.ebay.com/ebaymotors/ws/eBayI ... 471wt_1167
then hookup the fan from a atv or car as u mentioned.

[Shadow Catcher]

Marine axial fan http://www.deltatsystems.com/dtsp-Small_Axial_Fans.aspx

possible, http://cgi.ebay.com/NEW-DOOWON-10-TUBE- ... ltDomain_0

Do a search for Axial fans on ebay, there are a fair number that are AC and I would hazard a guess that most will swallow a good bit of rain with no difficulty particularly if you shroud them a bit. As you work on this there are a number of us that are interested so pictures and how you go about it will be of interest.

[theycallmemorris]

At $127 for that, about $30-$40 for the fan, and then the other materials, the price is really getting up there. The sound really isn't a huge problem, and the price isn't so much either. It's more of just another project that I have fun working on. Afterall, I already had two campers when I decided to buy the car hauler to convert...

Would something like this work?

http://cgi.ebay.com/12V-10A-Switching-P ... ltDomain_0

Keeping in mind that it would be mounted inside the frame and enclosure of the generator. I usually just drag the generator in front of the truck or behind a tree, so it all needs to be self contained.

Here is the computer version I had found.

http://cgi.ebay.com/12V-10A-AC-DC-Adapt ... ltDomain_0

What do yall think would work best? I need about 8 amps for the 12V fan, so these 10A adapters would cover that part, just not sure how they'd hold up.

[theycallmemorris]

I'll keep all of yall plenty updated with how it goes. Pictures and all. I'm a drilling engineer out at gas/oil rigs, so that's where I'm stuck right now. Which means by the time I get to go home, I should have a pile of boxes waiting for me and I can get things started on it all.

[Engineer Guy]

I have a pretty noisy 4.5 kW Generac Generator. I used it to run Tools and power an Avion Trailer while building our House. It's likely overkill to use for a future CT, but it is paid for.

A Website I can't find again this moment had details a fella wrote up. He welded an adapter from his similar-sized Generator and put the exhaust into a good ole 'Thrush' Car Muffler. He made a bracket to hold the Muffler to the Engine so that it 'moved' with Generator Motor vibration. That sounds like an important detail. I believe he had to remove the Spark Arrestor, so that's another legal/common sense consideration when out in the boonies.

Besides this solution being cheap $, he claims it reduced Gen noise very significantly such that he could use his Generator while camping w/o whizzing off his neighbors. I mentally 'bookmarked' this solution to try myself someday.

[theycallmemorris]

I do plan on adding some sort of take-off muffler from a streetbike, but that will be externally, and easily removable if I'm not wanting to mess with it for transportation. Most of the noise comes from the clattering of the engine though, so that is why I'm primarily focused on the enclosure.

I have come across several "squirrel cage" blower fans that may work out perfect, but need to make it back home to see the generator for what sort of clearances I have. With one of them, the generator noise would be even more self contained because of the way the air is vented through them without just having a large hole for a fan.

Did anyone take a look at those AC adapter links I put up? Do you think they would hold up? A 110V blower fan would work great if it would fit, but the ATV fans sure are reliable.

[Engineer Guy]

I've used all kinds of Fans on Pro Sound Equipment and other projects. Given that so much of Engine noise is 'bassy' concussive sound that is blocked only by dense 'mass', I doubt the non-line-of-sight subtlety of a Squirrel Cage-style Fan will make a whit of difference. Put a portable House Fan between your ear and a running Lawnmower as a test of this. Fans are fans. When I get around to quieting and transporting my noisy Generac, I'll figure out some way to mount and de-mount a Car Muffler quickly.

To K.I.S.S., I'd go with one of the nice 115 VAC Fans linked above and skip the Adapters. 'Switching' Power Supplies [P.S.] - the small type used for Cellphones and PCs - are fairly complex inside in order to shrink P.S. size. Temp specs matter, and those are all over the map. The simplest P.S. I have is an ancient Battery Charger & Starter from Sears. It outputs +12 VDC that is unfiltered, but fine for most stuff. A P.S. from Auto Zone or Checker Auto will likely take a beating and be inexpensive if the size suits you. Computer Fans, as linked above, are designed to run for thousands of hours at elevated temps, and represent one less thing to fail [the Adapter].

A Fan outlet port with sloped vents, like a House Furnace cover, would let air through - as it lets Furnace air out - while keeping rain off the 115 VAC Fan workings.

As opposed to building an impractical enclosure of dry-stacked Concrete Blocks - clearly not an option ;-0 - varnished pieces of MDF 'particle board' that click together on site are the densest portable material I can think of. They will block some Engine concussion; lighter mass material will not. If the top piece were sloped and longer than all the others, it would act as an 'awning' overhang and keep rain off the Fan and Genny. Knock down the enclosure to several loose pieces, and put a click strap and handle on them to carry easily w/o them taking much much storage space.

[Shadow Catcher]

At least with my Kipor the muffler seems to do a good job most of the sound seems to come from the engine itself.
EG how about using something like "Convoluted foam, smooth round cone-shaped peaks and valleys which redirect sound waves into the foam where the sound is converted to kinetic energy and absorbed. Convoluted foam gives you 4 times more absorptive surface than flat foams." http://www.singersafety.com

[Engineer Guy]

The convoluted Foam idea is interesting... We used an el cheapo version of such Foam and put it up on various Band rehearsal walls long ago. It's also kinda standard at lotsa Recording Studios and in anechoic chambers. As stated on that neat Website above, Foam is best on mids and highs; not concussive Bass. At 68 F degrees at sea level, sound travels at ~1,125 fps. The 42 Hz 'E' bottom string on my Bass Guitar produces a sine wave that is ~28' long for one cycle. So, the little 'hills' in Foam can't do much to attenuate such a long Bass note. Apt. or House Drywall does better, but not great...

I suspect they're using multiple layers of dense material to net specified ~12 -> 15 dB noise reduction, and that's where the ~$5,000- sales price goes in part for the Singer Safety product[s]. Indeed, most Genny noise comes from Engine 'clatter' vs. a muffled exhaust.

The main things that work are: 1) Put distance between you and the noise source. Doubling the distance halves the noise by 3 dB. 2) Make the noise source not be line-of-sight [the Genny down in a lil ravine?]. Vegetation doesn't do much to attenuate bass frequencies. 3) Put mass between you and the noise source: MDF panels; Hay bales; a few 30 gallon filled water barrels [I have some that were left on our Land]; etc..

I don't claim to know Honda's secret. But, their lil Gennies that power Tokyo Food Stall Lights and Cash Registers are amazingly quiet. I guess that's where some of the money goes in their selling price. For my future off-grid CT w/Solar, I plan to muffler a lil Engine and give this idea a try on cloudy or high Battery use days:

http://www.theepicenter.com/tow02077.html

We've lived the +12 VDC life part time in a Tuff Shed at ~9,000' and about all comforts are do-able at low voltage on the cheap. For occasional 115 VAC needs, I would put a stout Inverter in my TV as some wizard suggested here and run the TV engine briefly.

[Shadow Catcher]

EG I had looked at that web site but felt a bit concerned about exposed pulleys (curable) and just lack of capacity. Persistent effort on ebay found the Kipor contractor unit used for 300$. When I picked it up I found the only use it had seen was as a display model and it had never been started. It will put out 2400W and should with the Progressive Dynamics converter bring the battery up in an hour or two. With a full tank it will run 8 hours and is strong enough to power our AC.

[d30gaijin]

I have come across several "squirrel cage" blower fans that may work out perfect, but need to make it back home to see the generator for what sort of clearances I have. With one of them, the generator noise would be even more self contained because of the way the air is vented through them without just having a large hole for a fan.

Did anyone take a look at those AC adapter links I put up? Do you think they would hold up? A 110V blower fan would work great if it would fit, but the ATV fans sure are reliable.

Go to an automotive wrecking yard and look for a small automotive electric fan from a radiator (they come in all number of sizes) they are waterproof, move plenty of air, and then get a small 110v ac to 12v dc converter like you showed in the link you put up. That should keep the price fairly low.

Don

[theycallmemorris]

Go to an automotive wrecking yard and look for a small automotive electric fan from a radiator (they come in all number of sizes) they are waterproof, move plenty of air, and then get a small 110v ac to 12v dc converter like you showed in the link you put up. That should keep the price fairly low.

Don

I'm all for getting parts at a junk yard, but I found some of the 10 inch automotive fans on Ebay that are new for only $23, and they move over 1300 cfm, which is far more than any of the blower or computer fans. I think I'm going to settle with that and the converter. I'll have the fan blowing inward, with the converter mounted directly in front of the air flow. This should keep it cooled off a bit. That should do it for what I need to order, but I'll probably end up wiring in some sort of sail switch also so that if the fan were to quit, it would shut the generator off too.

As for the insulation mentioned above, I plan to do something along the lines of that too. A larger convoluted foam would be ideal if space was permitting, but all of this will be self contained in the area of the frame with only the aluminum diamondplate attached to the outside. I will probably go with something like dynamat or hood/firewall insulation. It's probably not the greatest for sound deadening, but given the size limitations and temperatures, it may be the best choice. I know this won't be as quiet as a Honda, but atleast I won't have to string it out as far from the trailer. There aren't usually others around where I camp, but if there are, atleast I won't be annoying them as much. The air conditioner and microwave are the only things that will be powered by the generator though. The lights and everything else are off of the battery, and I've got a solar panel that keeps that charged up. It's also nice having a diesel truck with two batteries in it that seem to run everything longer than I could ever need when it's still hitched up.

[Engineer Guy]

Sounds like a great and practical plan for power! Having the dual Batteries available is sweet, too.

The 'Subject' line above is a pertinent old saying amongst some of my pals in Tech Sales.