Charging EF Delta Pros from 48V Batteries: How to ensure overcurrent protection?

[mattT]

I'm curious about something similar in order to gain access to the 17 kWh HV battery on a PHEV via the 12V battery posts. The vehicle has a dc-dc converter capable of 2300W keeping the 12V battery and 12V systems powered. But at 12V/190A, too much for the DP solar input. If I install this boost converter on the vehicle, I could charge the DP at ~720W (48V x 15A) through the XT60i input.

DC-DC Boost Converter, 12V to 48V

DC-DC boost converter series on sales, output current from 1 amp to 20 amps to select, 10-25V wide input voltage range, is designed to step up 12V DC to 48V DC, high transfer efficiency and stable performance.

www.ato.com

 

[DarrylG]

But at 12V/190A, too much for the DP solar input.

These figures are not too much for the DP solar input. The Delta Pro will accept 11-150V and will only pull the amperage the Delta Pro can handle which is ~15amps from the solar input or 8amps if using the DC car charger cord. (The only difference is a data pin polarity.). Just like the 1 amp light bulb on your car is connected to the same system. But the 190 amps does not blow out the light bulb.

However the DC to DC converter you listed would allow you to pull more power into the Delta Pro by increasing the voltage 4x. So instead of 12x15=180 (actually ~196) you would be able to pull 48 x 10 = 480 or I would go for a DC to DC converter with close to 20amps available to make sure the DC unit is not overly stressed and give your max of 48 x 15 = 720 watts.

Check out: https://diysolarforum.com/threads/ecoflow-delta-pro-charging-from-a-switching-power-supply.43369/

 

[mattT]

I believe I could charge two delta pros with one of these voltage "buck" boosters off my phev.

12V/24V to 48V 40A 1920W DC DC Step Up Converter Voltage Regulator

Wide input voltage from 11 to 35V Work for appliances from 0AMP to 40AMP automatically 100% full rated power 100% full stable output current 100% burn-in test High-efficiency up to 96% Waterproof sealed Cooling by free air convection Surface mountable 3 years warranty Over-current, over-voltage...

daygreen.com

 

[DarrylG]

Yes. That seems like that would work. The converter is capable of 40 amps and two delta pros would be pulling around 30amps leaving a nice overhead.

You also could consider a pure sine wave inverter, converting your 12v DC to 120v AC and just plug your Delta Pros into it to recharge. This is my personal emergency power solution for my PHEV and I have found having the normal household electricity useful in many other situations as well.

 

[mattT]

I considered that route but the double voltage hub needs to be turned off or unplugged when AC charging.

 

[Brucey]

Can we connect the 48v battery to the external battery expansion port on the Delta Pro? Or will it confuse the Delta Pro/BMS? Because that probably doesn't have the power input limitations of the solar input?

 

[DarrylG]

Can we connect the 48v battery to the external battery expansion port on the Delta Pro? Or will it confuse the Delta Pro/BMS? Because that probably doesn't have the power input limitations of the solar input?

The external battery expansion port has proprietary connections and communications between the units. There have been some trying to reverse engineer it, but it would be difficult to figure out.

 

[1ram]

Hi!

Long time lurker, first time poster.

Context:
I have two Ecoflow Delta Pros that I connect to our house via the Double Voltage Hub (DVH) and a transfer switch.

I'd like to charge my Ecoflow Delta Pros from my 48V server rack batteries using each Delta Pro's PV input (XTi 60 connector). Given that the Delta Pro's SCC limits amperage to somewhere between 15A and 16A, I should be able to charge each Delta Pro with somewhere between 700W and 750W.

I've already browsed through related posts but couldn't find what I'm looking for.

Where I need help:
What stumps me is how to protect each Delta Pro from the potential 100A of each server rack battery. I'd like to connect 3x 48V 100 Ah server batteries in parallel. If I'm not mistaken (I'm a DIY solar beginner), that means that these batteries - when connected in parallel - can output up to 300A (3x 100A). And while each Delta Pro's SCC limits input current to about 16A, I want to put something between the batteries and each Delta Pro to make sure that the Delta Pros are protected in any case.

1) Do I need a T-Class fuse between batteries and each Delta Pro for this?
2) If so: would it have to be rated for 1.25 x 300A at least? Which rating should it have? 16A?
3) Is there an alternative to using T-Class fuses?
4) Do I need anything else in terms of overcurrent protection between the batteries and the Delta Pros?

Thanks for reading.

James

Did you connect them to the same 48V bank, or does each DP require connection to their own bank?
I ask because DP can not share a common PV input - not sure how they would respond to a steady battery bank, but on the face it would seem like they shouldn’t care since it won’t be voltage hunting..

 

[JamesTheCrow]

Did you connect them to the same 48V bank, or does each DP require connection to their own bank?
I ask because DP can not share a common PV input - not sure how they would respond to a steady battery bank, but on the face it would seem like they shouldn’t care since it won’t be voltage hunting..

I connected all batteries in parallel to two bus bars and connected each DP PV input to the same busbars.

 

[DBarr]

farmhand said:
Sorry for the misunderstanding.

Rephase; After learning I am able to add batteries to charge the Eco after dark, I now hope I can use the outhouse-battery-bank's charge controller's 10A rated "load" output directly to the Eco.

Newbie here with a question, You are charging the 48V battery with solar with a charge controller and then you hook up the LOAD Terminal from the charge controller to the Ecoflow XT60i port. Correct? This is what I want to do but I did not know if it would work. If there is a better way please let me know.

 

[JamesTheCrow]

farmhand said:
Sorry for the misunderstanding.

Rephase; After learning I am able to add batteries to charge the Eco after dark, I now hope I can use the outhouse-battery-bank's charge controller's 10A rated "load" output directly to the Eco.

Newbie here with a question, You are charging the 48V battery with solar with a charge controller and then you hook up the LOAD Terminal from the charge controller to the Ecoflow XT60i port. Correct? This is what I want to do but I did not know if it would work. If there is a better way please let me know.

I'm not sure if your question was directed towards me - if so, here's my setup:

solar panels to charge controller
charge controller to busbars
batteries to busbars
delta pro pv inputs to busbars