DC or AC generator for lipos

jfro

Aerial Fun
I'm thinking of selling my home 3500w generator (used 1 time in 10 years) and buying a smaller / quieter unit for charging lipos when flying.

Honda makes a small unit which is purported pretty quiet but it's also too expensive.

I looked at some 12volt gas driven units, and they are less expensive, but not sure if I've found a quiet one yet.

For charging a couple 6s batteriers and 4s in the field, I'm usually not drawing more than 24-30 amps. Is the gas driver 12 volt units being used or are peeps buying ac generators and then taking their power packs to drive their chargers? Guess I'm looking for the experience and wisdom of the forum here on whether it's advisable or not to use a 12 volt system.

Thanks in advance....
 

CdA D

Member
If you drive to the field then you could attach your charger to the vehicle battery. A 12v sys will take a bit longer, but if your not in a hurry..... If you use your vehicle battery be sure to start the vehicle or at least once in awhile. I think that the chargers are AC units, but I'm not sure that they won't work with DC. A couple of extra battery packs might be cheaper. I have a small folding table to put my charger and packs on and use a set of jumper cables to extend from the vehicle to the charger. That way I'm not getting the engine heat. Good luck.
 


Tuomas P.

Member
The Honda is great but the Kipor IG2000 works too. I also have an 300W sine wawe inverter in my van that I use feeding a charger while driving. Also the generator could be installed in the van so that the exhaust fumes are directed outside-it could be run anytime then. So its a AC 230 set as my chargers are then fed 25 volts from the power supplys.
TP.
 
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jfro

Aerial Fun
I'd like to get the honda eu2000, but it may be more than I can spend. I like it cause it's quiet and big enough for what I need. The Kipor looks interesting, but it seems to have some service issues, although that may not be an issue cause this will get light use. I may just hall my big sucker around, as it's 3500 watts and on wheels.

The other thing I was wondering is if they make a generator that just outputs 12 or 24 volts. I'd assume it would be a little less money, but not finding much info about them on the internet. Not even sure it would be practical or if they make something that's quiet.
 

g60jet

Member
I'd get a split charger for my car like a caravan system. then put a second battery in my boot. that way you can charge on the move or stationary and not risk your cars battery level.
 


g60jet

Member
I would never charge a battery inside my car! Outside always.
BMW and merc's have their batteries I the boot/trunk. As long as it's fixed and vented it's fine. Wouldn't do it in estates car granted. The charge rate from a car isn't gonna make it go bang and your terminals are secured unlike home charging with clip on connectors
 

jfro

Aerial Fun
I'm not so much interested in charging in my car or off my car battery.

I'm still wondering if they make gasoline 12v chargers. Not ac, but 12 volt.
 

meng

Member
The 6s battery is 22 volts. I dont think you would ever get it charged from a 12v system. I would go for the inverter.
 

kloner

Aerial DP
Inverter generator like eu2000 is way better than any stator type for this kinda thing.... if it was a skill saw or fridge would be one thing, but for electronics.... you want inverter type. yamaha has em, honda makes some nice ones. even in the bigger sizes, on any set in america there is either a bunch of big hondas or some mega diesel type and it's probably an inverter type. It's cleaner power, btteries will charge like at home.... i ran a genny like you mentioned having and it tore up my packs not fully charging consistently. they shake alot, usually noisy, just generaly not nice to use

i've never heard of what your asking about in a 12v genny,,,,

http://www.electricgeneratorsdirect.com/power/inverter-generators.html

I've bought a few generators form that place, never any problems
 

jfro

Aerial Fun
Kloner, thanks. I was looking for someone who had some knowledge or had tried the non inverter route.

If money were no object, I'd buy the Honda eu2000. That would be my #1 choice. Right now I have a heavier generator that I can wheel into my van and can handle some of my needs in my home if power goes out. Had it for 8 years or so and only needed it once for the home. Am thinking maybe to sell it and go with smaller unit.

They sell the Honda eu2000 for the same price locally that most of the internet folks sell them at. $999. Used ones seem to command a pretty high price. IMO, part of the magic of the Honda is it's pretty compact and it's quiet.

Since it won't be getting heavy use, I'm looking into the less expensive smaller/quieter units. Since I'm not in dire need, I will keep looking for a used one or an alternative to the more expensive units.

Thanks everyone for the suggestions & info.
 

kloner

Aerial DP
you will see slight deals on used hondas in craigslist. I've never came across a bad one renting them so my guess is used is ok, but you only save $200 and won't have a warranty....They are dead silent, might not make since sitting here talking bout it, but listening to it in the field is a whole nother level, especialy when your working

the advantage of internet is alot of times shipping is free and there is no tax....

You got the right idea, the choice is yours and you have a good educated mindset about the tool....
 

jfro

Aerial Fun
you will see slight deals on used hondas in craigslist. I've never came across a bad one renting them so my guess is used is ok, but you only save $200 and won't have a warranty....They are dead silent, might not make since sitting here talking bout it, but listening to it in the field is a whole nother level, especialy when your working

the advantage of internet is alot of times shipping is free and there is no tax....

You got the right idea, the choice is yours and you have a good educated mindset about the tool....

Ok, got lucky and found a barely used (looks brand new and oil was clear) Honda eu2000 for $750. Couldn't pass on it even though didn't want to spend that much. Can charge 2 - 6s batteries at 2s pulling around 1200=1300 watts and stayed on eco mode for a short test, so stays quiet & will run 8 hours on 1 gallon. Figured it's like a good Canon lens which hold its value for years. Hopefully will probably sell it in 3-5 years for around what I paid for it as I've seen very used/ beat ones going for $750-$825.
 


kloner

Aerial DP
there little ones are 48 kilos, make 110 watts and you can't even find a price.... that usually means if you gotta ask......

fuel cell technology is still awefully new at this point at the consumer level

the eu run forever on nothing,,, you'll dig it
 

mongo

lost soul
may be a little late to the party, but any genset that has electric start, also has a 12v alternator circuit to charge the start battery.
 

R_Lefebvre

Arducopter Developer
Inverter generator like eu2000 is way better than any stator type for this kinda thing.... if it was a skill saw or fridge would be one thing, but for electronics.... you want inverter type. yamaha has em, honda makes some nice ones. even in the bigger sizes, on any set in america there is either a bunch of big hondas or some mega diesel type and it's probably an inverter type. It's cleaner power, btteries will charge like at home.... i ran a genny like you mentioned having and it tore up my packs not fully charging consistently. they shake alot, usually noisy, just generaly not nice to use

i've never heard of what your asking about in a 12v genny,,,,

Sorry, but this is just not correct. AC motors do not like square wave electricity. So fridges, saws, etc. They run on it OK, but they end up running hotter than they would on a proper sign wave. You can actually burn out a motor if you run it at full load for too long on a square wave. However, electronics, like battery chargers and computers, really don't care. Why? Because the very first step in the power chain is to rectify the AC back to DC. The rectification does not, or should not, care if it's square wave or sine wave. This is just a common myth perpetuated because as always, some people think "you get what you pay for", and since they are powering expensive "delicate" electronics, they think they need a true sine wave inverter.

Anyway, I recently picked up the Champion branded 2000W inverter generator for $530 at Costco. I didn't get it because it's sine wave, but because it's quiet which is what I wanted. I also didn't want to spend Honda money. Lots of RC heli guys use these and they actually have a pretty good reputation. I think it's not quite as quiet as the Honda, but it's pretty quiet.

may be a little late to the party, but any genset that has electric start, also has a 12v alternator circuit to charge the start battery.

Every AC generator I have ever seen has DC supply. The problem is it's always very low power. For example this Champion only puts out 8A. That's 96W DC. Not much. My 4000W loud generator isn't much better at 10A.

I wish somebody would make a nice little DC generator. So simple... All you need is a motor and a GM 130A single-wire alternator which you can buy for $100 retail. I'd like to have one to charge the battery on my camper. It would only take a few minutes per day at that rate. Right now, I take my smart inverter charger running off the inverter generator... It's stupid.
 
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kloner

Aerial DP
whatever it is, in the field on my 3500 watt generac it never makes it to 24.9v and chops off, at home on the wall i get 25.2 all the same except the outet....
 

R_Lefebvre

Arducopter Developer
That could be a lot of things. If your DC rectifier is really simple, then it's just a simple AC/AC step-down transformer, into a rectifier bridge. So the voltage coming out is dependent on the voltage coming in. If the line voltage in your house is 120V, and the generator is putting out 110V, there's your difference. Square wave or not, doesn't matter to the voltage. A sophisticated DC Rectifier would have an active front end that can regulate the DC voltage better. In any case, like I said, once you pass through a DC rectifier, square wave just does not matter.
 

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