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MPP LV6548 charging

I browsed the thread above, you mentioned 64 CATl cells (4 x 16S, I assume) didn't see where you may have mentioned the Ah size of your batteries. Typically the charge rate for LFP cells is 1C and below. Ideally charging at 0.5C and below is best for longer life. I understand that when running a generator you would wish to charge as fast as possible and shut off that noisy machine. For example, if your CATL cells are 100Ah then I would set the chargers at 50Amps each and no more. That cuts your charging demand down to 10KW.
As far as the house, typically the continuous load for a breaker should be no more than 80%. So you should limit your house demand to 19.2KW. That said, Is your house all electric? Do you have propane or Nat Gas? At this point we are just guessing. I highly recommend actually testing the PEAK and AVERAGE current draw on your house with something like an Emporia Energy monitor that will keep track of usage and will produce a graph. The entry level device with 2 x 200A CT's is only $69.99. I'm using one of their 8 CT systems.

Lastly, one of the trade offs with MPP Solar and other value priced Inverters is the lack of some advanced features like Gen Support. Rather than spend a bunch of money on a massive generator, it would be better to consider managing the system and maybe consider some load control rather than the perhaps unrealistic goal of 100% "Plug and Play" operation.
 
I browsed the thread above, you mentioned 64 CATl cells (4 x 16S, I assume) didn't see where you may have mentioned the Ah size of your batteries. Typically the charge rate for LFP cells is 1C and below. Ideally charging at 0.5C and below is best for longer life. I understand that when running a generator you would wish to charge as fast as possible and shut off that noisy machine. For example, if your CATL cells are 100Ah then I would set the chargers at 50Amps each and no more. That cuts your charging demand down to 10KW.
As far as the house, typically the continuous load for a breaker should be no more than 80%. So you should limit your house demand to 19.2KW. That said, Is your house all electric? Do you have propane or Nat Gas? At this point we are just guessing. I highly recommend actually testing the PEAK and AVERAGE current draw on your house with something like an Emporia Energy monitor that will keep track of usage and will produce a graph. The entry level device with 2 x 200A CT's is only $69.99. I'm using one of their 8 CT systems.

Lastly, one of the trade offs with MPP Solar and other value priced Inverters is the lack of some advanced features like Gen Support. Rather than spend a bunch of money on a massive generator, it would be better to consider managing the system and maybe consider some load control rather than the perhaps unrealistic goal of 100% "Plug and Play" operation.
They are 280ah cells, so if I understand that math correctly, 120a is less than .5c.
Im building a house, so i can't really test my usage at this point. I understand I'm best to limit usage, and i don't plan to run at 100% loads for extended periods of time, but the instances where the water heater kicks on while the oven is on is what I'm preparing for. There is no gas or propane, propane is an option in the future, but im going to try to do without.
 
Thanks for the info. Technically yes you could charge those 280AH cells at 120A but would need a BIG generator as you already pointed out . In this case my advice would be to try and find a good used 20KW WhisperWatt generator with the Isuzu Diesel. These are very quiet and fuel efficient so if it has to run for 4-5 hours to charge your batteries while supplying the house so be it. Maybe set your 4 chargers at 50Amps each and leave the other 10KW for the house. Of course you may have to turn off your water heater from time to time.

I've been in the construction industry for over 20 years and was an industrial process engineer before that. I wanted to share a couple of other thoughts with you and hope it doesn't sound condescending or offensive in any way, It's just that my Project Manager mind is speaking.
Specifically energy efficiency. Its always cheaper to save a KWh than it is to produce one and save it in a battery.
For example, the WhisperWatt I mentioned above even used is still an expensive machine. Perhaps consider how to reduce electrical consumption in the first place is a better way to spend the same money. For example, what about a heat pump water heater. Why is propane not an option now? Why are solar panels not an option now? If you can avoid the need for a $20,000 generator by spending the money elsewhere that is a better course of action. my 2 cents.
Regards,
 
I appreciate the suggestions, and understand reducing kw usage is the best way to save money and improve efficiency. But, that's not really what i was trying to ask. I'm trying to wrap my head around what it's going to take to keep my house online while the batteries are charging, weather it's going to be running on the inverters or the generator directly.
As far as big generators go, I'm leaning towards a pto generator for one of my tractors, i just don't know how big I'll be looking for.
Propane is an option, but so is electrical service. The end goal is to be self sufficient on solar and making my own electricity. I can't make my own propane.
I realize I don't make my own diesel for the tractor running the generator either, but buying propane appliances i eventually intend to switch to electric seems as counterproductive as bringing in grid power when I intend to be go off grid. At least the tractor and generator are/will be useful in other aspects of the farm.
 
I appreciate the suggestions, and understand reducing kw usage is the best way to save money and improve efficiency. But, that's not really what i was trying to ask. I'm trying to wrap my head around what it's going to take to keep my house online while the batteries are charging, weather it's going to be running on the inverters or the generator directly.
As far as big generators go, I'm leaning towards a pto generator for one of my tractors, i just don't know how big I'll be looking for.
Propane is an option, but so is electrical service. The end goal is to be self sufficient on solar and making my own electricity. I can't make my own propane.
I realize I don't make my own diesel for the tractor running the generator either, but buying propane appliances i eventually intend to switch to electric seems as counterproductive as bringing in grid power when I intend to be go off grid. At least the tractor and generator are/will be useful in other aspects of the farm.

DID YOU EVER FIGURE THIS OUT???
 
In reviewing the user manual for the LV6548 I noticed an issue that is not clearly defined. Specifically WHAT condition(s) trigger a battery recharge, so we have to make some logical assumptions. Since menu #01 is set to SBU that enables menu items #12 & #13.
#12 is the voltage setting at which the Inverter will switch back to Utility or Generator (Pass Through or LINE mode) and theoretically start charging the battery.
#13 is the voltage setting at which the Inverter will consider the battery fully charged and switch back to Inverter mode and draw from the batteries.
Try these settings:
01 = SBU
12 = 51V (range is 44v to 51V) Seems like NO battery charging from generator will occur until batt voltage falls to this threshold.
13 = 55V (range is 48v to 62V)
16 = SNU (NOTE: this menu item states that charger source setting is valid ONLY if the Inverter is in LINE, Standby or Fault mode. Otherwise the batteries can ONLY be charged if solar is available) Therefore even with your generator is running, if the battery voltage has not fallen to the value set in #12, charging will not initiate.

Let me know if this works.
 
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DID YOU EVER FIGURE THIS OUT???
Not yet. I had my system partially setup temporarily, I'm in the process of moving it to its permanent location and plan on looking into it further once I have it setup again. I emailed Mpp solar, they didn't have a immediate solution, but they didn't say that the inverters won't do what I'm trying to do either. They asked for data logs from watchpower, but I've been unable to supply those since I've taken the system apart. Once I get up and running again, I plan to send logs and hopefully they'll have a solution. Another member on here has contacted me and offered to help once I'm running again as well.
 
Not yet. I had my system partially setup temporarily, I'm in the process of moving it to its permanent location and plan on looking into it further once I have it setup again. I emailed Mpp solar, they didn't have a immediate solution, but they didn't say that the inverters won't do what I'm trying to do either. They asked for data logs from watchpower, but I've been unable to supply those since I've taken the system apart. Once I get up and running again, I plan to send logs and hopefully they'll have a solution. Another member on here has contacted me and offered to help once I'm running again as well.

some of the guys on this topic had some good ideas ..we have a MPP Solar LVX 6048 that we are trying out to see if we want to get away from using all these EPEVERS ... so far - not looking good ....
 
I have tried working with MPP to get my LV6548s to charge and invert simultaneously. MPP has told me the hardware internal to the unit does not support converting and inverting simultaneously.
 
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