Gas powered 12Volt charger

[kbellve]

You would think there would be a ton of these things, a simple gas powered 12volt charger. What is easy to find is the 120AC/12V generators like the Honda e1000. The e1000 puts out less than 10amps on the 12V DC line. A car's alternator can put out from 50amps to 100+amps. The examples below put out 50 or 55amps, but there are versions that go beyond 100amps charging.

What I am thinking is getting is getting a 12V gas powered charger for my camper. My camper already has a 2000 watt A/C inverter that runs from 4 6V batteries. For extended dry camping, it would be nice to recharge the batteries in a few hours. Using solar is mixed, especially in highly wooded areas. Charging the batteries with my truck would take about 40hours (10amp/hrs for 40 hours for 400amp/hr battery pack).

So, after a search, I found serveral gas powered 12V chargers. The best one that I like seems to be only in Australia. No idea of the cost.

http://www.christieengineering.com.au/2.5hp.htm

The next one is a chinese knock off that I can get for about $300, but I think available in the US. It has lower noise output than the one above.

http://www.christieengineering.com.au/YK50A.htm

There are plans to make your own with a simple lawnmower engine and an alternator.

[adventureduo]

Too cool!

[pskhaat]

There are plans to make your own with a simple lawnmower engine and an alternator.

Cool product! I was going to say that I've seen a few DIY kits to attach a single-wire alternator to a small Briggs&Stratton. It'd be interesting to use a redundant matching alternator from the vehcile that could be poached if need be.

[Lynn]

Edit: Pskhaat types faster than I do...

Just thought I'd include a link to a site with info on homebuilt DC generators:

http://theepicenter.com/tow02077.html

They sell parts.

Also, another option I am planning on investigating would be to get a mil surplus 28V DC generator and regulate it to 12V.

But I think a home-made one could be smaller than the mil surplus units, and easier to maintain from a parts availability standpoint. Another advantatge to the home-built is that you could use the same model of alternator on both the genset and on your vehicle, so if your vehicle alternator goes out you swap out with the genset.

[kbellve]

US seller of the chinese knockoff:
http://www.batteriesareus.com/index.php?main_page=product_info&products_id=6730

Here is a version made in the USA, but expensive:
http://www.epowerchargerboosters.com/page2.html

[teotwaki]

I am wondering about the purpose of having a gas powered 12V charger?

Surely not to bring on an expedition? I have dual batteries in my rig and I can force the second battery on if I had to give myself a jump start.

Bringing along a AC generator and a (AC-powered) good battery charger might give you more use out of the generator than a 12 volt specific unit where you had to run an inefficient DC to AC inverter.

[Lynn]

I am wondering about the purpose of having a gas powered 12V charger?

Surely not to bring on an expedition? I have dual batteries in my rig and I can force the second battery on if I had to give myself a jump start.

Bringing along a AC generator and a (AC-powered) good battery charger might give you more use out of the generator than a 12 volt specific unit where you had to run an inefficient DC to AC inverter.

It depends on how long you plan on staying in one place, what your individual AC / DC requirements are, whether you want to run your vehicle engine just to charge batteries, etc.

Running an AC generator and battery charger may be more inefficient, if your primary needs are DC.

[kbellve]

I am wondering about the purpose of having a gas powered 12V charger?

Surely not to bring on an expedition? I have dual batteries in my rig and I can force the second battery on if I had to give myself a jump start.

Bringing along a AC generator and a (AC-powered) good battery charger might give you more use out of the generator than a 12 volt specific unit where you had to run an inefficient DC to AC inverter.

I beg to disagree. Check the pages for the outback generator. Guess where they go? The Outback in Australia!!

I think it is more efficient to go gas->12 Volt->Batteries->inverter to 110V AC. More of my appliances need 12V than I need 110 A/C. My 12V appliances include my water pump, furnace, hot water heater, refrigerator, and lights. My 110V AC appliances is my microwave, and TV/Satellite dish. So, it makes more sense to produce 12V power than to produce A/C power only to be converted to 12V power later.

Pros:
1) It puts out 5x as much amps at 12V compared to a A/C generator.
2) Easily charge your batteries faster using less gas.
3) Why pay for inverter technology in an A/C generator when you already have an inverter?

An AC generator would take forever to charge your 12V batteries. As I said, the EU1000 charges less than 10amps with the DC output. The UE3000 puts out 12amps at 12V. If you go A/C to a battery charger, you would get even less. My 110V AC charger does about 6amps at the 10amp setting. With my 2000watt (3000max) inverter connected to a 30AMP 120Volt AC source charges my batteries at 30amps max.

My truck will charge the batteries via the trailer connection at about 10-15amps at 12V.

If you goal is to recharge your batteries, than you can't beat a 12V gas powered charger. I believe it is more efficient, and cheaper, assuming you already have an inverter.

I could fully recharge my camper's battery once/week while dry camping. With an A/C generator, I would have to run it nearly once a day.

For an A/C generator, at 10amps/hrs, it would take 40hours to recharge my batteries versus 8 hours for a 12V charger.


Oh, cons?
1) Doesn't include a inverter.

[BajaXplorer]

Why would I not want to use my trucks alternator to recharge my auxilary battery? I could also upgrade my trucks alternator for less than $300 to 130 amps.
Am I missing something here?
BX

[kbellve]

I don't think this is useful for a truck with a dual battery system, unless you kill both batteries and need a way to charge them perhaps.

Let me just add..this is for large battery systems for things like trailers and campers designed for extended dry camping.

[hinoranger]

Personally, I find that my 120V needs in the field are minimal and easily met with a small inverter.

There are a couple of places that make a 12V- only, or better yet, 12V& air conditioning compressor diesel powered unit for marine applications. That would be sweet.

[teotwaki]

Okay, since I don't own a trailer I had not considered having to recharge those types of 12volt systems, especially with multiple parallel batteries. My truck has a 130 Amp alternator so it could easily recharge extra batteries if needed but running 8 cylinders is less efficient than 1 or 2 in a small genset. I can imagine that a gas generator versus solar power has already been debated with the bulk and cloudy day issues being the bigger negatives.

If a well-equipped trailer has an inverter then a 12 volt-only generator is not too specialized.

An earlier comment about a military 28 VDC generator is not a great solution as regulating that down to 12 volts introduces more losses. Maybe get a mil 28v generator and then replace the actual generator with a 12 volt unit of similar physical size?

[ntsqd]

About 40 years ago my granddad took a Delco 100 amp Generator (& regulator) & put it on a frame with a 3HP Tecumseh using a V-belt drive. We used it mostly to charge farm implement batteries when getting the implement ready for the next season's use of it.

Other than noise that system sounds like it would work for what you want. Were it me, I'd use a Delco 17SI Alternator. They're around 100-120 amps and big enough that you aren't likely to hurt one in long charge cycles.

[kbellve]

I found a US distributor for the Christie Outback generator...not a cheap generator for even the smallest one.


http://www.generatorjoe.net/subcatmfgprod.asp?0=635&1=631&2=-1

The price is $699 plus $550 for the freight from Australia...

uhm..not worth it. The chinese generator at $300 seems more attractive.

[njtaco]

I know this does not help with the efficiency question, but your batteries will generally last longer if SLOW charged, to keep heat down, as opposed to your goal (I'm presuming) to FAST charge them. This means ditching your 6V wet cells (I am assuming wet here) and investing in a high quality AGM that can take 15V plus (from the Christie Engineering site) if you want to fast charge your bank of energy.

Otherwise, I think your are on the right general track in skipping steps between gas/LP/diesel and your 12V goal. I'm not sure the cost/benefit will work out in real life, though.

On the motorhomes I've had the pleasure to work on ( <<== note sarcasm) the charge line to the coach batteries was generally protected by a 30A fuse or CB. This implies that even the deadest of battery banks could only charge at rates lower than this. Of course, YMMV.

Good luck on your search, and keep us updated. Despite my words, I do think there is a potential use here...

[Tucson T4R]

I have a bank of four AGM batteries in my trailer. I'd be concerned with throwing too many amps at them during the charge. Right now I use a Honda EU2000 generator that runs a built in smart charger in my trailer that is designed to charge AGM batteries. Seems to work fine for me.

And yes, I know a 2000 watt generator sounds like overkill....believe it or not, that was to be sure my other half can run her blow dryer!:shakin:

[njtaco]

And yes, I know a 2000 watt generator sounds like overkill....believe it or not, that was to be sure my other half can run her blow dryer!:shakin:

I'm sure this small sacrifice was appreciated...:)

[kbellve]

Generally you can charge at 10% of your battery amp-hr capacity. I have 440 amp-hrs, so I should limit my charging to ~44amps. The smaller generaor maxes at 55amps, but in real wworld use, I am sure it is less and you coud always throttle it down.

[njtaco]

kbellve,

Are you figuring your capacity by taking four 6V batteries, 110aH each, to get 440aH? IIRC, (I'm fuzzy on this) if you are using the batteries in a 12V configuration, you actually end up with 220 aH. This is because aH capacity adds only when in parallel, not in series. 10 percent is then 22A to charge, which is why I was thinking 55A is high. Am I off on this? It has been a while since I was schooled on it...

I still say it is a cool idea, worth looking into. :)

[kbellve]

njtaco, you are correct about halving the AH when you go from 6V to 12V, but you were 1/2 off of the AH capacity of my batteries :)

I believe my batteries are 220 AH each at 6Volt.

Just checked...they are Interstate U2200 batteries which have 232 AH. 4 * (232/2) = 464 AH.

[njtaco]

That's good news! :jumping:

[kbellve]

I am glad I see plenty of interest on this forum. So far, 0 posts from my post on ih8mud...

[njtaco]

Different market?

[3IMOH]

Folks,

I purchased one of the yk-50 gas battery chargers from "batteries are us".

http://www.batteriesareus.com/index....oducts_id=6730

It was non-functioning when I received it. One of the cable posts was broken, and the led screen displayed gibberish when running. I called the seller to see about getting another unit, and he was incredibly rude. He did send me a new cable post, and he said he would order another display panel. Said it would take a couple of weeks to get in. It has been 2 months now and I have not seen (or heard) anything from him. I just called today to see what the status was on it, and he ended up hanging up on me! I am not very confident I will ever see this thing work. Unbelievable.

I don't really know what to do...does anyone have any suggestions? He has refused to take this unit back, so I think I am probably out $300.

Just wanted to share this in case anyone else was thinking of doing business with them...

-Howie

[Robthebrit]

I have an IOTA 90Amp converter, just plug it into a generator or mains and you are charging at 90amps. Its only about 4x6x10 inches, about the size of an inverter and fits under the floor in the camper. Its also a perfectly clean power supply as well as a charger so its safe to run while you are using power. The gas powered alternator would have the same benefit which can't be said for all battery chargers. A 1.8kw Brigs engine probably takes more gas than the E2000 and makes a whole lot more noise. I think the converter is the best of all solutions as you can charge silently if mains power happens to be available, you can use any generator of your choosing, its also one less thing to carry.

A better way to carry a spare alternator would be to charge the aux battery with a second identical alternator and do away with the isolator, replace it with an jump switch so you can join the battery banks should either of the alternators fail. No tools required, just flick a switch and continue driving. You might have to disconnect the power connector to the broken alternator if its shorting or making dirty power.

You can also use the switch to join the batteries and alternators if you need lots of power for winching or fast charging (useful when idling the engine or driving a short distance). When winching, with 2x130amps from the alternators you'd be pulling really hard on the winch before you even touch the batteries.

This is how my mog is set up, it uses a solenoid for the transfer. I have never had to use it because both alternators work but its good to know its there.

Rob

[LXRACR]

I already have a EU2000. I also have a Vector 50 amp charger in my garage. Couldn't I run that off the generator and have the same thing?

[BiG BoB]

...You can also use the switch to join the batteries and alternators if you need lots of power for winching or fast charging (useful when idling the engine or driving a short distance). When winching, with 2x130amps from the alternators you'd be pulling really hard on the winch before you even touch the batteries....

Wouldn't the alternators both see each other as fully charged batteries and just regulate back?

Sean

[elcoyote]

If you are thinking of going the DIY route, you won't go wrong with these nice low rpm units from these folks. I have used their stuff before for some alt energy projects.

http://www.windbluepower.com/category_s/1.htm

[peekay]

as someone already mentioned, why not just get a 1000w or 2000w Honda with a battery charger ac to dc? Those Hondas will run forever, plus, you have the versatility of 110 vlt.

alternatively, just get a jumper cable and use your vehicle? I've idled for hours on end, and it didn't appear to use hardly any gas.

[JIMBO]

:lurk: Let me throw this in for grins--

--I use SOLAR and I camp in the Norther Sierras, yes I have to move the Pnl several times during the day, but,it has no moving parts and is QUIET !!!


--
http://i294.photobucket.com/albums/mm83/jimbowby/IMGP0644-1.jpg

--I have a battery in my trailer that will "drop in " my Xterra, should it's battery fail and I have a 25' cord to the panel for moveability, with a 7 amp controller and a DC voltage solid state ckt to kill all load power when the Battery gets below 12.4 volts, then the SOLAR just charges the battery--

--I have a SOLAR 1.5 watt panel to keep the battery "topped off" during travel and a "battery condition meter" to show the state of the battery at any time--


--
http://i294.photobucket.com/albums/mm83/jimbowby/IMGP0644a.jpg

--Seems to work flawlessly and QUIET-

--
http://i294.photobucket.com/albums/mm83/jimbowby/IMGP0655.jpg

--I would think seriously about SOLAR and perhaps dual batt's and deep cycle--

---:bigbossHL: :bigbossHL: --JIMBO

[hinoranger]

as someone already mentioned, why not just get a 1000w or 2000w Honda with a battery charger ac to dc? Those Hondas will run forever, plus, you have the versatility of 110 vlt.


well, arn't the small Honda generators actually 12v run through an inverter? That would make running a battery charger off of one a little redundant. I've wondered about rewiring a Honda 1000 or 2000 without the inverter, theoreticaly should be 50+ or 100+ amps of DC.
Anybody know if that should work?

[Mike S]

I have a bank of four AGM batteries in my trailer. I'd be concerned with throwing too many amps at them during the charge. Right now I use a Honda EU2000 generator that runs a built in smart charger in my trailer that is designed to charge AGM batteries. Seems to work fine for me.

And yes, I know a 2000 watt generator sounds like overkill....believe it or not, that was to be sure my other half can run her blow dryer!:shakin:

I am considering the Honda EU2000i genset to charge a pair of 6V AGMs in my trailer, which will run an inverter, fridge, lights. The Honda can be bought for abot $1200 USD, and is fairly quiet.

Starting from stratch, would you buy the same again? Which smart charger are you using?

M

[Mike S]

Folks,

I purchased one of the yk-50 gas battery chargers from "batteries are us".

http://www.batteriesareus.com/index....oducts_id=6730

It was non-functioning when I received it. One of the cable posts was broken, and the led screen displayed gibberish when running. I called the seller to see about getting another unit, and he was incredibly rude. He did send me a new cable post, and he said he would order another display panel. Said it would take a couple of weeks to get in. It has been 2 months now and I have not seen (or heard) anything from him. I just called today to see what the status was on it, and he ended up hanging up on me! I am not very confident I will ever see this thing work. Unbelievable.

I don't really know what to do...does anyone have any suggestions? He has refused to take this unit back, so I think I am probably out $300.

Just wanted to share this in case anyone else was thinking of doing business with them...

-Howie

If you bought using a credit card, contact your CC company and cancel the transaction. The prick will be docked for the purchase price.

M

[hinoranger]

Anyone? I havn't had time to fina shop manual for the EU series, but what voltage does the actual generator run at? Are the losses minimal enough that running a battery charger off an inverter equipped generator like the Honda too minimal to worry about?


well, arn't the small Honda generators actually 12v run through an inverter? That would make running a battery charger off of one a little redundant. I've wondered about rewiring a Honda 1000 or 2000 without the inverter, theoreticaly should be 50+ or 100+ amps of DC.

Anybody know if that should work?

[mog]

I have a Coleman Ultimite 2-stroke (40cc) generator. I don't know if you can still get them as they are 2-strokes (crime against nature in California)....but:
Pros: Small (16"x16"x16"), light (20lbs) 24 VDCs @45amps, 12 VDC @ 90amps, 110 VAC @ 10amps, cheap (<$200 when Costco was selling them)
Cons: Very noisy! Hard to start (I'm spoiled by Honda generators)

I originally bought this for my 24VDC Unimog (since gone :( ), but with using and being spoiled by the Honda ' quiet series ' generators, the noise of this one is LOUD. Not something you would want to run in camp (unless you have a bunch of 2-stroke motorcycles running around to mask the noise). But great output for the size and weight. Perfect for emergency jump-starting, etc. But the Honda always goes along, and the Ultimite is a garage queen. If I every need 24VDC again, it is a good option.

[hinoranger]

Mog, interesting. How long ago did you buy yours?
The website only shows 3 larger models.

What's the fuel consumption like?

[James86004]

How about a 12V generator that runs off firewood?

http://www.nyethermodynamics.com/nt6/index.html

[mog]

Mog, interesting. How long ago did you buy yours?
The website only shows 3 larger models.
What's the fuel consumption like?

Quite awhile ago, maybe 6+ years.
No idea on the fuel consumption, I've only run it 15 minutes or so at a time (a plus side of the high output).
An internet search turned up "1.5 hours on a tank"....and I'd guess the tank to be a quart?
I think the Ultimite will find a home on my new trailer build. I'm running 'surplus' Falcon F-50 aircraft batteries (we replace them after 3 years regardless of condition), so they are more then happy to accept 90+ amps (split down to 12VDC from 24VDC) for charging. I will be able to run for days on battery power along, and top 'em up quickly if needed.

[Carlyle]

So my question is, has anyone wired a Honda type generator to produce 12 volt power only and bypass the inverter? What power, in amps would it produce?

[ntsqd]

I've no idea if this is how the Honda's are or not, but newer gensets are no longer tied to rpms in multiples of 60. They synthesize the AC frequency and vary the rpm to suit the load. Later model Dometic gensets are made this way.

If this is the case with the Honda's, wiring around the inverter will require new logic and a new control board.

[allnew2me]

Here is a good explanation of how the Honda, and also other invertor/generators work.

http://www.arrl.org/files/qst-binaries/QS0608Kleinschmidt.pdf

[ntsqd]

Here is a good explanation of how the Honda, and also other invertor/generators work.

http://www.arrl.org/files/qst-binaries/QS0608Kleinschmidt.pdf
Handy article, Thank you!

[LXRACR]

Purchased the gas powered charger through their website paid for shipping and everything). It has been 1 month without anything. I have emailed the company times without a single reply, I guess I will be contacting my credit card company! Crappy business!

[Carlyle]

Boy that blows chunks. Was hoping to hear better things, I hope your ccc comes through and reimburses you. I just ordered a Yamaha 1000 in propane for solar augmentation. If I could figure out the above article, maybe I could charge my batteries quicker with it...

[LXRACR]

So, I got stiffed. The company never sent the charger ($375.00) and the guy emails me back, mocking me. I put in a dispute at my credit union but they state I have to wait another 30 days....DO NOT buy from that company, they are thieves.....

[orangeTJ]

What I am thinking is getting is getting a 12V gas powered charger for my camper.

been there, done.... :jump:

built my own.

pics coming soon once I find them

[orangeTJ]

here's the pics.......

the motor and alternator are attached to a purpose built metal base, then that is rubber shock mounted to a larger wood base so it would work better on uneven ground.

Marine style externally regulated alternator using a 3 stage "smart regulator" to maximize output of the alternator. 5hp briggs & stratton motor

http://i162.photobucket.com/albums/t271/dohdrz/misc/gen1.jpg

http://i162.photobucket.com/albums/t271/dohdrz/misc/gen2.jpg

http://i162.photobucket.com/albums/t271/dohdrz/misc/gen3.jpg

[taugust]

I just got the latest Northern Tool catalog that shows a direct DC charge cord for the Honda EU series generators. There is also one for the EM and EG series. It looks like it plugs into a special socket.

[Carlyle]

I can't seem to find that, can you point me in the right direction?

[VikingVince]

Over July 4th, I was beach camping for 8 days/7 nights. I knew I'd lose my aux battery after about 5 days. (brought along a big cooler with block ice) I tried running my truck for 2 hours to recharge the aux battery...didn't work adequately...I guess just not enough rpm's/alternator amps at idle.
So clue me in...why wouldn't these 12v chargers be a good solution with the situation I just described? A lot cheaper than a Honda generator.

A simple logistical question...whether a generator or charger, you have to run it outside of the vehicle. On the 12v charger, the battery terminal connectors appear to be on fairly short leads. My aux battery is in the front of my truck bed...how do you get the connectors to the battery (I'm NOT taking the aux battery out of truck)...just connect another set of jumper cables to the charger leads?...or would that type of connection result in a current loss?

[taugust]

I can't seem to find that, can you point me in the right direction?

If you are looking for the Honda EU charge cord, it shows up in the Northern Tool master catalog as item #166730-2901, $19.99. Unable to find on the website. Try calling 800-556-7885. The website only has basic specs on the generator, no details.

[orangeTJ]

About 40 years ago my granddad took a Delco 100 amp Generator (& regulator) & put it on a frame with a 3HP Tecumseh using a V-belt drive. We used it mostly to charge farm implement batteries when getting the implement ready for the next season's use of it....

About 10 years ago I built one using a 5hp B&S motor, with 120 amp marine alternator and 3-stage regulator.

It works well, but I actually have no use for it anymore and want to sell it.

edit: opps, I see I posted pics already, http://expeditionportal.com/forum/showpost.php?p=259485&postcount=47

[Alten]

You would think there would be a ton of these things, a simple gas powered 12volt charger. What is easy to find is the 120AC/12V generators like the Honda e1000. The e1000 puts out less than 10amps on the 12V DC line. A car's alternator can put out from 50amps to 100+amps. The examples below put out 50 or 55amps, but there are versions that go beyond 100amps charging.

What I am thinking is getting is getting a 12V gas powered charger for my camper. My camper already has a 2000 watt A/C inverter that runs from 4 6V batteries. For extended dry camping, it would be nice to recharge the batteries in a few hours. Using solar is mixed, especially in highly wooded areas. Charging the batteries with my truck would take about 40hours (10amp/hrs for 40 hours for 400amp/hr battery pack).

So, after a search, I found serveral gas powered 12V chargers. The best one that I like seems to be only in Australia. No idea of the cost.

http://www.christieengineering.com.au/2.5hp.htm

The next one is a chinese knock off that I can get for about $300, but I think available in the US. It has lower noise output than the one above.

http://www.christieengineering.com.au/YK50A.htm

There are plans to make your own with a simple lawnmower engine and an alternator.


The Christie Engineering chargers are now built and sold in North America by ALTEN Battery Chargers (Ferndale, WA). They're available in gas or diesel, in 12, 24 and 48 volt models up to 120 amps. The Honda models use the commercial GX series motor and come with the 3-year Honda warranty, serviceable at any Honda dealer. You can also find a complete YouTube video demonstration of the chargers by Googling "Alten Battery Chargers", or here:

http://www.altenbatterychargers.com/products/battery-chargers.html

Drop us a note, we'd be happy to answer any questions.

Cheers.

PS The Chinese knock-offs were a result of an Australian distributor bypassing the manufacturer. The Chinese manufacturer was able to replicate absolutely everything including a dent in one of the components that came from shipping the original over for reproduction. Unfortunately they couldn't quite get them to work properly and almost all of the Chinese knock-offs ended up being returned to the Australian dealers.

[NikonRon]

I would just use a Schumacher 25 amp battery charger coupled with my Honda EU1000 generator. It would charge 2-Trojan 6-volt batteries in a couple of hours. Ron

[Carlyle]

Hi Ron,

I don't see how the Honda 1000 could charge at 25 amps. I have a similar generator and it will produce a maximum of about 3 amps on 110 and 9 amps on 12 volt.

[NikonRon]

Carlyle, the battery charger puts out 25 amps when plugged into the 110 volt outlet on the generator. The dedicated 12 volt charger for the Honda does not put out much, which is why I found it more feasable to purchase a seperate 110 volt battery charger which you could also use at home or at a campground where you had shore power. Ron

[Carlyle]

Ron,

I never professed in my life to having more than a rudimentary knowledge of electricity. But how does your or my 1000 watt generator produce 25 amps through a charger when it currently produces a maximum of 10 amps on 12 volt? Where does that extra power come from?

[NikonRon]

The generator is not putting out 12 volt power, it is producing 110 volt power to a charger that puts out 12 volt power at a charge rate of 25 amps. Ron

[Carlyle]

Ron,

I just guess I'm a little ignorant, but if a 1000 watt generator only produces about 3 amps on 110, how does plugging in a charger bring it up to 25 amps? If this is the case, I'll get a charger like you are spec'ing next week.

Carl

[peekay]

Ron,

I just guess I'm a little ignorant, but if a 1000 watt generator only produces about 3 amps on 110, how does plugging in a charger bring it up to 25 amps? If this is the case, I'll get a charger like you are spec'ing next week.

Carl


Carlyle, you need to compare watts, not amps. I don't have a lot of electrical knowledge myself, but here's what I do know.

A 1000watt generator puts out:

83.3 amps at 12 volts (1000 watts/12 volts=83.3 amps) OR

9 amps at 110 volts (1000watts/110 volts=9 amps)

Therefore, 25 amps at 12 volts is certainly within the capabilities of the 1000 watt generator.

[hinoranger]

Th]http://www.altenbatterychargers.com/products/battery-chargers.html[/URL]

Drop us a note, we'd be happy to answer any questions.



Any chance of model more along the lines of the Honda EU1000- low noise, moderate fuel consumption, say 40A- capacity in the future?

[Carlyle]

Thanks for the help Ron and I think I have it figured out now. Charger between the generator and the batteries and hooked through the shunt. To further augment, put a 1000 watt inverter between vehicle batteries and the charger with a shut off relay so that the house batteries charge properly while driving down the road. Any input?

[NikonRon]

Carl,
Aren't your house batteries being charged while you drive from your vehicle's alternator? I suppose the inverter and battery charger would charge them quicker. I always tried to not let my batteries drop below 50% discharge, doesn't take as long to bring them back up and is better for the batteries. Ron

Really like the Alaskan!

[Carlyle]

Hi Ron,

Here is an answer to that borrowed from the Outback Power Systems Forum, which is the system I am using:

The issue is that the “12 V” batteries at 77 F (25 C) need about 14.4 V (and sufficient current) measured at the battery terminals at the transition between bulk and absorb stages. “13-14 V” less “0.5V to 1.0V” (~12.5 V to 13 V max at the batteries?) won’t do the job. If the batteries are cold, they’ll need an even higher charge voltage.

Unless there’s a positive voltage difference between the charging source and the batteries, they won’t charge, no matter how big the alternator. The result is batteries that measure 12.5 V at rest after being “recharged” instead of 12.8 V or so.

And for me I have learned that if my batteries are down they charge very very slowly. :smiley_drive: My system will shut down if it drops below 75% which has not happened yet.

Glad you like the Alaskan, so do I!

[NikonRon]

The inverter may really help you out in your situation. Do you have solar panels also? The Yamaha is really the trick I think, and so quite you really hardly notice them running. I realize your operating on propane, but I always put mine 50 ft. away from camp and ran an extension cord. Also helped to have something between the generator and camp to block the sound. ( a rock, tree, vehicle,etc.) Ron

[Carlyle]

I am running a pair of 85 watt solar panels as well, but they are affected by weather, time of day and time of the year versus your location. Great when at peak efficiency, but that is sporadic. The generator is really not very loud and with the right charger I should have to run it only a couple hours every other day or less, unless I watch too many late night movies.

BTW, the propane conversion is sweet and one less fuel type to bring along.

[Jnich77]

Why not take the motor off a garden tiller (or snow blower) and hook it to a car alternator?

[ick]

For those with larger battery banks I can see a need for this product. I have a 450 Ah house bank, 1800 w inverter and no genset on a boat. Charging the bank is really a pain as I need to run the engine at high idle for 8+ hours to fully charge the bank (my 65amp stock alternator probably puts out closer to 40 amps when it's hot).
Some of the big reasons this is an ideal solution:
#1. No room for solar
#2. On the water so jumping from a vehicle isn't an option (even if it were, the recharge time would be crazy).
#3. Cost - why buy a generator and a battery charger? If I could find a cost effective generator that had a built-in transfer switch and electric start I would consider it.

Current setup

Shore Power -> Inverter w/ Transfer switch -> A/C load
..........................╚House bank
................................╚DC load

Desired setup #1

Shore Power -> Genset w/ Transfer Switch -> Inverter w/ Transfer switch -> A/C load
.................................................. .................╚House bank
.................................................. ......................╚DC load


I am thinking about making charger w/ a high output (200+ amps) alternator as my A/C load can reach 2kw which is quite a load on the D/C side.

Desired setup #2

Shore Power -> Inverter w/ Transfer switch -> A/C load
........................╚House bank
gas powered alternator ╝╚DC load


I'm really happy with the setup right now as the inverter is nice quiet power but when I have large load needs like microwave and air conditioning it would be nice to fire up a unit to keep my batteries up.

[wrcsixeight]

Interesting thread.

They say it takes 1 horsepower for to turn an alternator and produce 25 amps, So you would need an 8 hp motor running at max rpm to turn the 200 amp alternator fast enough for it to approach it's claimed 200 amp output.

I couldn't imagine an 8 hp Briggs and Stratton roaring away in the hold or on deck.

And say it is roaring along, and your inverter is asking for 2000 watts from the battery bank. So you fire up the B&S to pump amps back into the batteries which then send it to the inverter.

Sounds like it would be very hard on the batteries.

I hear you about the cost, but a 2000 watt Honda could serve your AC loads, and replenish your battery bank with a big charger. Quietly. Walmart sells 40 amp vector chargers for pretty cheap. You can put 2 on your battery bank. There is a guy over on RV net who runs 2 vector chargers at the same time off a honda 2000 charging the same battery bank. http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/23799919/gotomsg/23800766.cfm#23800766

You could easily run a 80 amp charger off of a 2000 watt Honda.
Keep in mind your batteries could only accept that kind of amperage if they were very low, and only for a while, but not if they are old, abused and sulfated. AGM batteries could accept much more and faster, but again, cost.

But anything has to be better than running your engine for hours and hours on end for relatively little charging.

If you had a generator, you would not need to abuse your battery bank as much either, and would be able to recharge it easily quietly and quickly those times you do.

Another option would be to put another alternator on your current engine, one rated at higher amperage, and put on some 1 gauge or 0 or 00 gauge wiring to pass the amps.

[Carlyle]

I now use a 30 amp smart charger with my 1000 watt generator. This combination will take my batteries from 75 to 100 percent in a little over four hours. The alternator of the truck charges the bank slowly at best and only used as an addition when traveling. Perhaps a system could be used with an inverter to bring power to the charger, but this seems inefficient at best.

[whatcharterboat]

Did you guys in the US never get the baby 2 stroke Honda 35Amp @ 12VDC charger?

I think they took them of the market about 10 years ago. They had double the poles so only need to run at 1500rpm, not 3000 like normal. IIRC. Very quiet. Like a new Honda EU 1000 4 stroke. Very very compact too. About 13" long x 10" higb x 5" deep. My brother still has his. Won't part with it. Maybe it was a "Honda DC400", not 100% on that. Black in colour. Sure, not as powerful as a Christie but still a fantastic thing to keep in the vehicle.

I got a 350watt / 240VAC version "Honda EU350" . Look exactly the same but is metallic red in colour. Only used it for flood lighting our campsite. Same low noise output. BTW mine still has a little 6A 12VDC additional output as well like most AC gensets

[oldosc]

Morning gentlemen,
Reading this thread with interest.. In my last vehicle, I installed a Sterling Alternater battery charger, clever sod..charges your leisures off the alternater, at 40/60 amps on ticker over. had it four years, when I ran low((we camp sauvage) (that's eurospeak for tucked up in a wood.)) have a dvd player to watch pre records at night. Also have two semi electric bikes, and an electric outboard for my sea cat....the sterling coped well with about 1 hour tick-over a day.
However, Chausson bit broken in Ukrane due to roads slightly excentric.
Bought new Hymer, due to warenty cannot adapt alternator so bought sterling Battery to Battery charger..clever sod again, will charge leisure batteries at 40 amp whilst moveing..NOW only problem is I am informed modern diesels do not like 1 hour tick over, the bores become glazed and rings do not bite.
I offer the above as an observation..worked for me Company is STERLING Battery co
I am saving up for a fuel sell..v expensive..but Lady J threatens poison If i try a gererator.

[TCcruzn]

You can get alot more charging amperage out of the inverter type generators by plugging a high amp smart charger into the AC, instead of using the DC output. The smart charger will also regulate the amperage going into the battery which helps your batteries last longer.

[Jnich77]

So lets see..used tiller engine and a used alternator.... for less than 100.00 I would think you can build one.

[762X39]

So lets see..used tiller engine and a used alternator.... for less than 100.00 I would think you can build one.
Ok, so has anyone actually done this and made it happen or is this just academic?
I seem to remember a military 24vdc charger that was powered by a small petrol engine to charge 24 volt systems (radio truck batteries or something). I think you need a few more pieces like a charge controller, fuel tank, cage to hold it all together... might be easier to buy something already built.:coffee:

[Jnich77]

Ok, so has anyone actually done this and made it happen or is this just academic?
I seem to remember a military 24vdc charger that was powered by a small petrol engine to charge 24 volt systems (radio truck batteries or something). I think you need a few more pieces like a charge controller, fuel tank, cage to hold it all together... might be easier to buy something already built.:coffee:

I have seen one many years ago in Colorado while camping on BLM land. The guy had a tiller motor with a pulley on it and a GM alternator from summit racing. The motor has the built in gas tank, and you set the throttle by hand. The alternator does everything else, no different than when its in a car. I woudl imagine you could toss in a small 10" electric fan to keep things cool and it woudl be a done deal.


Hell, when something shows up with a motor I like on craigslist cheap I am going to build one to solve this...lol. If I can get a good running motor, and figure out the RPM's I need it shoudl be a very easy build.

[dwh]

Ok, so has anyone actually done this and made it happen or is this just academic?

It's been done a million times. These guys sell some parts for the DIYer:

http://theepicenter.com/tow02077.html

[Jnich77]

It's been done a million times. These guys sell some parts for the DIYer:

http://theepicenter.com/tow02077.html
That website is awesome!!!

[magentawave]

I now use a 30 amp smart charger with my 1000 watt generator. This combination will take my batteries from 75 to 100 percent in a little over four hours. The alternator of the truck charges the bank slowly at best and only used as an addition when traveling. Perhaps a system could be used with an inverter to bring power to the charger, but this seems inefficient at best.

Are you still using this system to charge your batteries? If so, what is the brand/model of the 30 amp charger you're using with the generator?