Whats a good 48v battery charger

[RCinFLA]

When you look for a charger above 1kW to be run on a generator you should look for one with a good power factor rating.

Generators, inverters, and transformers are actually rated for VA not watts. A poor power factor requires a generator nearly twice the rating of charger.

A typical uncorrected power factor charger has a power factor of 0.6. A good PF corrected unit is greater than 0.9.

 

[me3]

When you look for a charger above 1kW to be run on a generator you should look for one with a good power factor rating.

Generators, inverters, and transformers are actually rated for VA not watts. A poor power factor requires a generator nearly twice the rating of charger.

A typical uncorrected power factor charger has a power factor of 0.6. A good PF corrected unit is greater than 0.9.

If it's switch mode (ie. feels light, not heavy), then it will be much weirder than that. They tend to draw weird harmonics from the peak voltages to charge the supply capacitors through the rectifier. Means often the cycle is almost no current for 70% and only drawing current for 30% or less. Makes PF calcs almost impossible to my knowledge. The current draw is not even close to sine. Add that to an inverter generator and your loads can be "interesting".
They can include active PF correction, but that actually reduces efficiency, and tends to be there for permitting / compliance reasons for the grid. I have never seen info on how that affects generators / inverter generators.

 

[RCinFLA]

If it's switch mode (ie. feels light, not heavy), then it will be much weirder than that. They tend to draw weird harmonics from the peak voltages to charge the supply capacitors through the rectifier. Means often the cycle is almost no current for 70% and only drawing current for 30% or less. Makes PF calcs almost impossible to my knowledge. The current draw is not even close to sine. Add that to an inverter generator and your loads can be "interesting".

Uncorrected PF supply. All the power is supplied by the short, high current pulses (blue). The short, high current pulses require generator of greater power capability.


Switch mode chargers can have power factor correction. Most computer power supplies these days have PF correction (driven by European regulations)


PF correction is usually a half sinewave pre-boost switcher between rectifier and filter capacitor to charge the filter cap with a near sinewave current profile.

A low freq hybrid inverter/charger has a good PF for charging. Not all high freq hybrid inverter/chargers do have good PF.

 

[Supervstech]

Growatt6048 has 80A charger, with solar inputs, outputs 6000va 240V and is under $1000...

 

[Stewfish]

It your fan noisy (fast speed)? And sometimes never slow down / shut off when charge finished (stay noisy)
At the full charge rate - how much heat comes out?
Does the charge rate slow down to about 50% after 30mins due to heat?

Mine is out in the garage so none of that noise stuff matters to me. If I get a low charge day (100% off grid) then I start the generator to run all night and let the 2 gallons of gas burn through and shut off, thus the AIMS turns off. I can still get all 6000w of power without then generator trying to run loads also and stalling out. Which was happening when I tried to use the MPP genny input. I don't need a 6000w genny that uses 8 gallons of gas a night. All the gen does is charge - well, or to run power tools etc sometimes.

I mounted the charger with the fan on the bottom blowing heat up and out to get best of both worlds (heat rising up like a heat sink style charger and fan helping it rise). Its usually 20 to 30 deg in my garage this winter on average at night so thats a cold breeze to keep it cool. In the summer our desert is always sunny and we didnt need a charger until the recent winter storms in Dec. that flew east.

You could always dremel/ grind off the top grid/Outlet for more air flow. Same for the fan side and or add a 110mm quieter fan.

 

[Stewfish]

When you look for a charger above 1kW to be run on a generator you should look for one with a good power factor rating.

Generators, inverters, and transformers are actually rated for VA not watts. A poor power factor requires a generator nearly twice the rating of charger.

A typical uncorrected power factor charger has a power factor of 0.6. A good PF corrected unit is greater than 0.9.

There a very very few 48v lifepo chargers

I guess for smaller generators you could get 48v 2000w MPP or growatt (MPP sister) and hook that up to the battery and just use the charger. I think the 48v ones all use the same charger with the same specs/paperwork when I was looking. I just didnt want to double my generator size and gas amount to be able to microwave dinner and/or also run the well pump for 2 minutes to fill my pressure tank while it's charging leading to a overloaded 3000w genny

 

[home skillet]

Aloha Fam,

Trying to help my friend get their battery bank charged from a basic gas generator.

It's a 48v battery bank 200ah, sealed lead acid batteries.

She does have solar but wants backup for extended cloudy days etc.

She already has a little gas generator. Dont know the specs.

To determine the charger size, do I take 120v from the generator and multiply it by the charger amps. Aka a 30 amp charger would charge 3600wh and the battery bank is 9600wh so charging would take 3 hours. Assuming the generator could handle that load?

Do my numbers make any since? And does anyone have a product recommendation for charging this battery bank off a generator. Something simple for intermittent use.

https://www.forklift-battery-charger.com
or buy a used single phase one on eBay

 

[Roswell Bob]

https://www.forklift-battery-charger.com
or buy a used single phase one on eBay

I wouldn't consider a charger without PFC when running from a small generator - power factor correction.

 

[home skillet]

I bought a 48VDC 120 amp for emergency situation. It worked fine when i tested it out. I run it with a 9500 WATT harbor freight predator. I think the Honda Wannabe is the weak link here....

 

[Fusion is the future]

AC Converter/Battery Charger 36/48V: The Inverter Store

Offering a large charging capacity, the AIMS AC Converter/Battery Charger 36V and 48V, 25/18 amps, handles multiple battery types across a range of applications.

theinverterstore.com

These are great standalone chargers. Variable output, so if you have concerns about load on the generator you can just turn the output down a little bit.

Nope, they are 100% crap

 

[Supervstech]

Nope, they are 100% crap

Oof, really? What issues have you had with it?

 

[Fusion is the future]

Oof, really? What issues have you had with it?

after 3 minutes working it was going in overload and stoped working , the overload protection and or max current control is terible ,

 

[Wet1]

Growatt6048 has 80A charger, with solar inputs, outputs 6000va 240V and is under $1000...

This to me makes a lot of sense... plus you have a spare inverter for your system in a pinch.

 

[Fusion is the future]

There a very very few 48v lifepo chargers

I guess for smaller generators you could get 48v 2000w MPP or growatt (MPP sister) and hook that up to the battery and just use the charger. I think the 48v ones all use the same charger with the same specs/paperwork when I was looking. I just didnt want to double my generator size and gas amount to be able to microwave dinner and/or also run the well pump for 2 minutes to fill my pressure tank while it's charging leading to a overloaded 3000w genny

PM3 48V Series - PowerMax Converters

PowerMax PM3 48V AC to DC converter charger for Off-Grid battery bank, on-board Golf Carts charger and to power 48V equipment - Lithium too

powermaxconverters.com

 

[Jack Rabbit Off Grid]

PM3 48V Series - PowerMax Converters

PowerMax PM3 48V AC to DC converter charger for Off-Grid battery bank, on-board Golf Carts charger and to power 48V equipment - Lithium too

powermaxconverters.com

I have the 12v 100A model of this in my RV and it works great. It use to be hooked up to 4 6v lead acid batteries. I have now switched over to a Chins 12.8v 300 AH. And it works just as well with it set at a voltage of 14.2v.

 

[Nobodybusiness]

You might want to look into a V5 AutoGen 48v DC Generator with max charge of 70amps.
Can charge any 48v battery chemistry.
Set your Bulk and Absorbtion settings, auto start stop, remote monitor and control via AutoGen app.
Here is a link for your reference.

V5 AutoGen 48v DC Generator | Smartest 48v DC Generator

V5 AutoGen Automatic Start 48v DC Generator. Designed to automatically startup and charge low battery banks. Accessible over wifi through our ...

dcautogen.com

Here is a video of the V5 AutoGen

I like these guys but dang you all are proud of them.
I ended up Getting an Alphagen DCX charger.

 

[time2roll]

This would be my pick:

https://www.trcelectronics.com/View/Mean-Well/NPB-750-48.shtml

Larger or smaller available depending on need or budget or power limit.
PF corrected, adjustable voltage, 2 or 3 stage charging.

 

[Fusion is the future]

I have the 12v 100A model of this in my RV and it works great. It use to be hooked up to 4 6v lead acid batteries. I have now switched over to a Chins 12.8v 300 AH. And it works just as well with it set at a voltage of 14.2v.

And i have to say their service is great , got my charger in Mexico , really a pleasure buying at this company .

 

[spruce_trees]

You might want to look into a V5 AutoGen 48v DC Generator with max charge of 70amps.
Can charge any 48v battery chemistry.
Set your Bulk and Absorbtion settings, auto start stop, remote monitor and control via AutoGen app.
Here is a link for your reference.

V5 AutoGen 48v DC Generator | Smartest 48v DC Generator

V5 AutoGen Automatic Start 48v DC Generator. Designed to automatically startup and charge low battery banks. Accessible over wifi through our ...

dcautogen.com

Here is a video of the V5 AutoGen

What range of increased fuel efficiency in charging can be expected using such a DC generator, as opposed to DC to AC to DC charging?

 

[Jack Rabbit Off Grid]

I just ended up buying the Champion 8.5kw whole house propane backup generator. Along with the Magnum ME-AGS-N. I chose this over the Autogen because I can power my PowerMig 210 welder with it when needed.

Other then powering a welder and satisfying my insurance company I really don’t need a generator larger then my Champion 3100.