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Best 48 Volt Battery Charger for EG4/GYLL 48 volt battery

I have a 20yr old eu3000is and can get ~2000w of continuous charging (~40a@50v) before it starts running unevenly due to overload. I use 2 x 15a@48v chargers + a 3rd one at 7a@48v = 37a of charging. If the battery is at 53v * 37a we get 1961w of DC.

Not sure of the losses of AC->DC so maybe the generator is doing another 15% - e.g. 2300w of AC into the chargers to get 2000w of DC into the battery.
 
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Old thread but if I have 2 48v batteries wired in parallel and 1 charger where do the charger leads go to. Any one of the 2 battery posts?
Thanks
 
Old thread but if I have 2 48v batteries wired in parallel and 1 charger where do the charger leads go to. Any one of the 2 battery posts?
Thanks
Depends on the core system topology.
I prefer to peer each of my batteries to the system busbars.
Code:
positive
|<->fuse<->battery.1<->smart_bms<->|
|<->fuse<->battery.2<->smart_bms<->|
|<->fuse<->charger<--------------->|
|<->fuse<->load<------------------>|
                            negative
 
Cabling only. I was thinking of using Polaris connectors for batteries and have separate leads come out of it to charger. Thoughts.?
same as a busbar?
 
Polaris are kind of expensive I’ll look for busbar setups more reasonable.
 
I have a 6 battery bank eg4 lifepower4. My question is can i hook a charger directly to the battery bank bus bars and charge ? Do I need more than 1 Charger hooked to the bus bar if I can do it this way. I want to charge (Off generator to battery charger) while my system is running and panels aren't making enough power to keep up the charge.
 
I have a 6 battery bank eg4 lifepower4. My question is can i hook a charger directly to the battery bank bus bars and charge ?
Sure.
See diagram in this post.
Do I need more than 1 Charger hooked to the bus bar if I can do it this way.
Depends how much current you want to charge with.
 
I want to be able to charge as quickly as possible and safely at the same time .
6 batteries x 100 amp hours * .5c charge rate = 300 amps.
You could charge at a rate as high as 300 amps.
If it was me I would charge at .2c which is 150 amps.
That means all your concurrent charge sources should not exceed 150 amps aggregate.
That means up to 3 batteries can be offline and you will still be within the .5c window.

BTW the best ac2dc charger is an inverter/charger.
 
What would be your recommendation ie brand? Could it be treated as a stand alone for charging only hooked to a generator?
For a smaller unit I like this.

For a bigger stackable unit I like this.

These are both premium products that integrate a ac2dc charger, automatic transfer switch and an inverter.
Won't you also need the inverter functionality?
 
This is an all in one which contains all the components of an inverter/charger and also integrates a solar charge controller.
 
For a smaller unit I like this.

For a bigger stackable unit I like this.

These are both premium products that integrate a ac2dc charger, automatic transfer switch and an inverter.
Won't you also need the inverter functionality?
I have 2x eg4 6500 trying to figure out how I can connect a generator to 1 or both inverters using 240v. Would i need to separate 240 wire from the generator to have 120v to each inverter? Or maybe another sub panel that separates at a breaker then outputs 120 to each inverter. I'm so confused. Lol
 
I have 2x eg4 6500 trying to figure out how I can connect a generator to 1 or both inverters using 240v. Would i need to separate 240 wire from the generator to have 120v to each inverter? Or maybe another sub panel that separates at a breaker then outputs 120 to each inverter. I'm so confused. Lol
I'll let someone with more experience on those all in ones guide you.
 
I have 2x eg4 6500 trying to figure out how I can connect a generator to 1 or both inverters using 240v. Would i need to separate 240 wire from the generator to have 120v to each inverter? Or maybe another sub panel that separates at a breaker then outputs 120 to each inverter. I'm so confused. Lol

Yeah, as long as it's a split-phase 240v (with also 120v volt from each hot to neutral), as not all generators have split-phase. Most consumer-grade generators sold in the US with 240v are split-phase with 120v as well.

Then yeah, do what you're indicating, have a small sub panel (can be just one 240v dual-pole breaker), and put a plug on the input side for the generator cord, and run each output leg to the separate inverter leg inputs and split the neutral there in that small breaker box.

There are some grounding considerations to make as well, depending a few factors, which there are other threads here we've talked all about grounding before (like if the generator will be considered a Separately Derived System or not)...

 
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