Best 48V AC-DC Charger?

[jharrell]

I understand that, but you'd need to set the voltage and current output. That way, it will stop charging once the defined potential us reached. If the voltage us variable and current fixed, it doesn't have a way of stopping barring BMS.

Charger or power supply is set to absorb voltage say 58.4v and battery is at 51.2v, so lots of current will flow more then the charger can provide, so charger goes into CC mode LIMITING current, once voltage of battery rises closer to set absorb voltage batteries will only accept current at LESS than max charger current setting and now it is in CV mode where by voltage is held and current slowly goes down as battery rises, the only way current could be held is to continue to raise voltage beyond your absorb setpoint since its not current goes down I = V / R.

Voltage is pressure, current is flow.

 

[time2roll]

One that understands the appropriate charging curve for LFPs and tapers off after 80%

How fast are you charging? Most chargers don't have the capacity to need the current tapered at the end. Charging at 2C+ this might be needed.

 

[42OhmsPA]

I read through the thread on this, and really don't plan/want to use the CAN bus interface. Am I wrong in thinking that all I need in addition to the unit, is wiring and protective devices?

No, that's how I'm running mine. I didn't get to the CAN bus, yet. I just turn it on and turn it off. It's not ideal but it works perfect for my needs.

I only plan to use it manually @ 120v. I'm guessing this would trip my 1500w generator using propane, if I don't have a way to adjust maximum current.

Yes, it would definitely trip. When I wired mine up for 120V it was pulling ~2kW on the AC side.
Post in thread 'DIY 'Chargenectifier'' https://diysolarforum.com/threads/diy-chargenectifier.56329/post-1134200

 

[time2roll]

Hello folks,

My LiTime 54V 18A charger is a piece of crap and I need to replace it so I can fully charge up my 48V batteries.

Any recommendations?

How else does the LiTime miss your expectations?

 

[Over9000]

How else does the LiTime miss your expectations?

You mean sides not working? I guess no other way.

 

[Wolfpack7483]

I'm looking at this unit instead.

Amazon.com

Too many failed units in the reviews for me.

 

[Over9000]

Too many failed units in the reviews for me.

That's why the search continues!

 

[wpns]

You will set the voltage of the power supply to a particular number, the maximum voltage you want to charge the battery to. You will set the current limit of the power supply to the maximum current you want to charge the battery at.

The initial charging, since the battery voltage will be less than the power supply voltage, will be current limited.

As the battery voltage approaches the power supply voltage setting, the current will drop below the current limit, and the voltage will be maintained at your voltage setting.

 

[Over9000]

You will set the voltage of the power supply to a particular number, the maximum voltage you want to charge the battery to. You will set the current limit of the power supply to the maximum current you want to charge the battery at.

The initial charging, since the battery voltage will be less than the power supply voltage, will be current limited.

As the battery voltage approaches the power supply voltage setting, the current will drop below the current limit, and the voltage will be maintained at your voltage setting.

Providing both parameters can be set, yes.

Any good units for this?

 

[Wolfpack7483]

No, that's how I'm running mine. I didn't get to the CAN bus, yet. I just turn it on and turn it off. It's not ideal but it works perfect for my needs.

Yes, it would definitely trip. When I wired mine up for 120V it was pulling ~2kW on the AC side.
Post in thread 'DIY 'Chargenectifier'' https://diysolarforum.com/threads/diy-chargenectifier.56329/post-1134200

Thanks. I may go ahead & get that one to play around with, then figure out if I want to add CAN bus later.

 

[wpns]

Providing both parameters can be set, yes.

Any good units for this?

Are you just looking for a battery charger, or a bench power supply? Any bench power supply from Amazon should have voltage and current settings.

You will want 60 V at whatever current you think you need.

 

[Over9000]

Are you just looking for a battery charger, or a bench power supply? Any bench power supply from Amazon should have voltage and current settings.

You will want 60 V at whatever current you think you need.

Whatever gets the job done without molesting my wallet.

 

[wpns]

Whatever gets the job done without molesting my wallet.

Which job is that? Topping off the batteries occasionally, or charging them on a regular basis?

 

[Over9000]

Which job is that? Topping off the batteries occasionally, or charging them on a regular basis?

Batteries are at 49.54V. Current charger is a piece of shit and won't get them any higher. Need 54V ideally.

 

[time2roll]

I have and recommend the Meanwell NPB series. Not the highest power, not the lowest cost. Does perform to specification.
https://www.meanwell.com/webapp/product/search.aspx?prod=NPB-1700

 

[Over9000]

I have and recommend the Meanwell NPB series. Not the highest power, not the lowest cost. Does perform to specification.
https://www.meanwell.com/webapp/product/search.aspx?prod=NPB-1700

Looks like it needs a computer input to control the charging.

 

[wpns]

I still can’t tell if the OP {wants, needs, desires, requires, demands} a float voltage lower than the charge voltage, AKA 3-stage ‘ intelligent’ charger, which might require him to tell is what the rest of the system is

 

[time2roll]

Looks like it needs a computer input to control the charging.

There are several good profiles using the dip switches. Yes for a few $$ more the programming is extensive.

 

[Over9000]

I still can’t tell if the OP {wants, needs, desires, requires, demands} a float voltage lower than the charge voltage, AKA 3-stage ‘ intelligent’ charger, which might require him to tell is what the rest of the system is

This is simple - my batteries are all measuring 49.5x V and I need to charge them to their float voltage. My current charger is a piece of crap and won't charge anything.

 

[pollenface]

how will it know when to stop?

I use timing switches.

 

[Over9000]

Timing switches? That wouldn't work for me, as there is too much calculation involved especially when there are automatic chargers available.

 

[pollenface]

Timing switches? That wouldn't work for me, as there is too much calculation involved especially when there are automatic chargers available.

It's not that involved really, you set an arbitrary limit (eg 2hrs @ 3.55v/cell) come back in 1hr 50mins to see how it's going. If still in CC mode give it more time.

 

[Over9000]

It's not that involved really, you set an arbitrary limit (eg 2hrs @ 3.55v/cell) come back in 1hr 50mins to see how it's going. If still in CC mode give it more time.

Just not for me. I'll find one that's more straightforward

 

[wpns]

This is simple - my batteries are all measuring 49.5x V and I need to charge them to their float voltage. My current charger is a piece of crap and won't charge anything.

Still can’t tell

 

[Over9000]

Still can’t tell

Not sure why!