Decent, inexpensive PSU or charger recommendations

[Sasa Duric]

I have 8 cell Eve LF304 (304Ah) pack in my truck and I need a grid charger as permanent installation alongside PV. Until now I have always dragged around my  20A bench PSU. 

I bought used Mean Well RSP-3000-24V on ebay but it came faulty. I have had bad luck with few other used switching server PSUs in past, so I am kind of tiered and broke from all the experimentation.

Is there any decent new chargers out there suitable for batteries like mine that can take up to 0.5C. I guess 80-100A would be decent and well below the 0.5C charging.

I am thinking about Polish made battery charger Magnum Dinamik 640 V2 that can charge 24V LiFePo4 with 100A, and have charging current adjustment. If set to LiFePo4 max voltage is 28V, but as SBMS0 take care of the cut-off, I guess I could set it at AGM/gell and than the voltage is 29.6V. The price is 220EUR which sounds attractive for 100A charger. As it has car start help function I expect it must be immune to the power surges thus of a good quality. 

https://spawarki-magnum.pl/dinamik-640-v2

[Dacian Todea (electrodacus)]

Do you need to charge at 0.5C?  Is this for emergency charging so you need to charge in less than 2 hours ?

There will be no reason for 0.5C charging if you charge overnight.

That thing looks like a welder and seems to be to light to be transformer based so likely it is inverter type.

Not sure if that thing can be controlled by the SBMS0 since that ON/OFF button may directly switch OFF the AC input current.

I will recommend for around the same price you get one of those 3000W hybrid inverter/chargers from china and use it as a charger only. It will have the same weight about 5kg and likely more reliable.

I have two of those hybrid type inverter chargers that I only use as inverters and they work everyday for many years (I think the oldest one is about 10 years).

Here is an example but there are under many brands with small differences. Just make sure it has an toggle switch ON/OFF button so that you can use that to allow SBMS0 to control it ON/OFF

https://www.aliexpress.com/item/1005006499664468.html  the   SCI-ECO-3200 will charge with 80A and should be fast enough.

If you want 100A charging get this as it is not that much more expensive https://www.aliexpress.com/item/1005008851815469.html  but is a bit larger and heavier.

You can check trough maybe hundred's of similar models as internally they use the same design and if you want to be sure it works with SBMS0 just post a link and I will take a look at it.

[Sasa Duric]

Thanks for the tip Dacian. I avoided these as I thought it makes no sense with SBMS0, but as I would like to upgrade my inverter as well, it actually makes sense now. I did not know they can charge from the grid.

I  was planing to have it as emergency charging, but not necessary 0.5C. I might add another battery, so bit more power would be better. 

Can you please explain why this is a problem:

m

"Not sure if that thing can be controlled by the SBMS0 since that ON/OFF button may directly switch OFF the AC input current."

Offer of those hybrid inverters is overwhelming. would this be good candidate: https://ebay.us/m/auuZXp

and this one: https://amzn.eu/d/a1zJysE

[Habana7]

There are plenty of good chargers, I would keep it simple and mainly for mobile use, isn't this something for you?

Op zaterdag 17 januari 2026 om 09:07:05 UTC+1 schreef sasa...@gmail.com:

[Sasa Duric]

Not really. It is underpowered. Honestly, I have not found many candidates that are min 80A.

[Habana7]

An IP67 waterproof Lifepo4 24V-50A fast charger underpowered?,  seems perfect to me, why do you think it needs 80A or more?

Op zaterdag 17 januari 2026 om 16:34:37 UTC+1 schreef sasa...@gmail.com:

[Dacian Todea (electrodacus)]

Yes both of those are good and they are actually the same just different brand and different arrangement for the connectors.

Here is a short review of mine https://groups.google.com/g/electrodacus/c/-ep59RSGjdo/m/LNlu0PsKAgAJ  also very similar to those and I used it for the past 5 years with no problem but just the inverter part as I do not have grid or a generator.

But you can not use it as both unless you add a SSR on the AC input and stop the charging that way.

You need to be able to control the charger and inverter separately.  I control the inverter ON/OFF trough the ON/OFF toggle switch. I just soldered two wires in parallel with the ON/OFF switch leave the switch on the OFF position and connect those wires to the EXT IO3 set as type 2 so that way the SBMS0 turns OFF the inverter/charger if battery is empty.

You will need a SSR on the AC input controlled by the EXT IO4 set as type 1 in order to stop the charging but still keep the inverter working.

The inverter charger that has proper separate control for inverter and charger are the Victron models but those are quite a bit more expensive than this things.   

[Sasa Duric]

OK. Thank you Dacian.

[Sasa Duric]

Dacian, I have bought Easun 4.2kW hybrid inverter. What would be a way to connect it if I wanna use it for AC battery charging and as a load: DC to AC? From the sbms0 point of view, it should be connected to a different points on a shunts. It is not clear to me if the  PV shunt is there just for a measurement of how much current load is pulling from the PV, and Load shunt still measures correctly the current going to the battery if I connect this Easun to a load shunt and use it as a charger and as the inverter.

[Dacian Todea (electrodacus)]

You will normally connect it to the battery shunt so where you connect the Loads if is mainly used as a load with occasional charging. The hybrid inverter works either as a charger or as an inverter not both at the same time since to do charging it inverses the flow trough the inverter.

If you have some other DC loads or another inverter then you may not see what those use during charging with the hybrid inverter.

This way the PV shunt is dedicated to solar charging so you know exactly how much energy you got from the Sun but not how much you charged with the Easun.

You can also connect it to PV shunt (assuming your PV shunt is rated to handle 4.2kW) and in that case you can log how much energy you pull in from the grid and the DC loads you may have will also be logged correctly but then when you use the inverter you will not be able to see the correct PV solar current assuming you also have PV solar.

In both cases battery current is measured correctly and so SOC calculation is correct it just affects Load's current measurement or PV current measurement depending on where you decide to connect it. If you have solar you normally want to know how much it produces so standard is to connect the hybrid inverter on the Load side.

The main problem is to control separately the inverter and charger.

For the inverter is simple you just open the front plate to access the ON/OFF switch on the side and solder to wires in parallel with the switch and leave that switch on the OFF position while the wires are connected to EXT IO3 set as type 2 and this allows the SBMS0 to turn ON or OFF the inverter in case of battery fully discharged.

To use the charger also you will need to add a SSR on the AC input and control that with the EXT IO4 or EXT IO5 set as type 1

So when battery is full the SBMS0 can disconnect the AC input and stop the charging to protect the battery from overcharge. This is good option for occasional grid charging while the much more expensive Victron inverter/charger have separate controll for inverter and charger meaning it can still bypass grid to your AC loads when battery is fully charged while that will not work with this type of hybrid inverters that do not have a separate ON/OFF for the charger.

[Sasa Duric]

Dacian, you said to use the charger I need to add a SSR on the AC input and control that with the EXT IO4 or EXT IO5 set as type 1. 
I have 2 options... one is this "40A" Chinese SSR that I don`t think I could trust to cut something that critical as charging, and another is decent contactor with 24V coil (Siemens 3RT2026-2BB40). What do I need in order to connect it to EXTIO4/5 and how exactly to connect it?
Could I use some MOSFET driver board. Once engaged, it pulls around 20mA. I suppose it has some inrush in the moment of activation, but I cannot measure that.

[Dacian Todea (electrodacus)]

Closing power seems to be specified at 5.9W for the Siemens 3RT2 https://media.distributordatasolutions.com/siemenscomplete/2023q3/documents/b0e79dfa4a32c4263d5e4f7c3c718e3fe0138f06.pdf  but so is the holding power that will be around 250mA so well above the EXT IOx capabilities of 50mA.   It could easily be driven by the DEXT if you have one and you are not using the type 5 for secondary level protection.

You can maybe use two of those SSR's one on the neutral and one on the live fire have the input's in series and a resistor also in series to protect the EXT IOx and wires.

My re-flow oven uses similar SSR's for many years with no issues switching ON/OFF 2000W of heating elements and that is at 120Vac. If is not getting hot under normal conditions and it works I do not see why it will fail.

If charging is at 3000W then 3000W/220V = 14A and if the SSR has a drop of around 1V that may result in 14W that needs to be dissipated as heat requiring a relatively large heat-sink for passive cooling.

[Sasa Duric]

That is good to hear. Is there a chance that if SSR fails, ot stay in the closed state?

[Dacian Todea (electrodacus)]

If it fails due to overheating the most likely state will be closed circuit. This is valid for all types of semiconductor switches including mosfets and what most likely is used in that SSR a Thyristor.

But a relay/contactor can also fail close circuit if the contacts get welded while switching ON under heavy load.

If you will be using a type 5 for secondary level protection none of the faults possible are relevant as that type 5 will just trip if either OVLK or UVLK is reached and so it will isolate the battery from all charge sources and all Loads by tripping breakers or opening contractors controlled by that type 5 EXT IOx