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Understanding MPP Solar charge settings for LifePO4 batteries

I have a LV5048 I don't see it listed as supported.
I am emailing Pierre right now, he said the LV6548 is supported.

He said "The LV6548 is supported and if your model has small differences which causes issues we will fix them as the software should be plug and play for all MPP solar inverters."
 
I have a LV5048 I don't see it listed as supported.
Hi Darren, a friend of mine emailed them and they offered a trial license. Then we tried it again for another setup and they gave another trial license. I suggest you mail them, the email is at the bottom of their website.
 
Hi Darren, a friend of mine emailed them and they offered a trial license. Then we tried it again for another setup and they gave another trial license. I suggest you mail them, the email is at the bottom of their website.
I got my "site" up. Pretty painless. But some wonky behavior for now. It thinks I have 3 inverters for some reason.

Can you see the site? https://jasonhc73-01.us.solar-assistant.io
 
Wow that's quite a step up from the lousy software I've seen before for MPP hardware. Was this a fairly simple install for you on your own Pi?
Extremely easy install. I tried on a pi 2 b but just didn't work. I bought a 3b+ and it worked fine.

The only hickup there was, was the very beginning, the pi didn't broadcast the SID. I had to add the network manually. Once I got it connected then I was able to configure its server to my wifi. After that it has simply worked. The parallel inverters caused a weirdness, but Pierre fixed it pretty quickly.

Everything is pretty much all server side. As far as I can see, the only thing the Pi does is send all the data to the cloud server.
 
Extremely easy install. I tried on a pi 2 b but just didn't work. I bought a 3b+ and it worked fine.

The only hickup there was, was the very beginning, the pi didn't broadcast the SID. I had to add the network manually. Once I got it connected then I was able to configure its server to my wifi. After that it has simply worked. The parallel inverters caused a weirdness, but Pierre fixed it pretty quickly.

Everything is pretty much all server side. As far as I can see, the only thing the Pi does is send all the data to the cloud server.

Hopefully it works well without Wifi (or just bluetooth). I have my 1012-MS installed in my teardrop and no networks where I camp.
 
Hopefully it works well without Wifi (or just bluetooth). I have my 1012-MS installed in my teardrop and no networks where I camp.
It has to have access to the internet. That is literally all the Pi is doing, sending the data in the inverter to the cloud.
 
It has to have access to the internet. That is literally all the Pi is doing, sending the data in the inverter to the cloud.


Talking about this method. Seems to indicate that once you activate the license, you can use the Pi's Wifi to monitor the system off-net.
 

Talking about this method. Seems to indicate that once you activate the license, you can use the Pi's Wifi to monitor the system off-net.
Maybe Bluetooth? But this seams to be only for getting setup so that you can configure the wifi access point.
 
I am new to all this. I recently received 8 each 280 Ah LiFePO4 batteries. The SOC was low by the fact that I was able to charge them with a 55 amp LiFePO4 compatible charger (Inteli Power 9100 Series Model PD9155 with the Charge Wizzard connected). I did 4 packs at a time (12 volts) using the charger and monitored each cell to be sure none ran away. After 4 hours or so one of the cells was nearing 3.6 volts so I turned off the charger (the knee is quick as I was aware of this and I was standing over the batteries with 4 VOM's monitoring - one for each cell). Next I hooked up all 4 cells in parallel and set a lab supply to 3.65 volts. After setting the supply to 3.65 volts I connected it to the parallel pack with #10 wire. The charge current was 10 amps. I kept charging until the current on the supply dropped to zero which took a while (like 4 hours or so). Once the current reached zero I kept the charger on for another hour. Then I removed the charger and disconnected the batteries. The voltage on each battery was 3.65 volts. Now after 2 days just sitting there the voltage on each cell is 3.53 volts. This pack is now ready to add the BMS. I will be using an Overkill Solar's 120 amp BMS which I just received in the mail last week.

I repeated this procedure on the second pack of four and I attained the exact same results

This is the top balancing recommended by Will Prowse. Snoobler is correct in his statements about fully charging at 3.65 volts for top balance and this is also verified by statements made by Will Prowse.
 
I have a LV5048 and am running 16S 150Ah LifePO4 aluminum cased prismatic cells. I have been running the system for a few weeks now and the cells are all well balanced. (I'm using a "320amp" ANT BMS)

I'm not understanding the behavior of the bulk and float voltage settings on the LV5048. I have program 26 set to 56.4v (bulk) and program 27 set to 54v (float).
I never see the battery voltage go above the float setting (54v). This seems of makes sense because that is an individual cell voltage of 3.375v - well within the safe max voltage and close to 100% SOC. However the bulk voltage setting translates to 3.525v per cell which is borderline high. I never see a voltage that high during charging. It never see the battery go above the float voltage setting...

The issue I am having is that the float charge voltage setting causes the charge current to drop off long before full charge is reached. The battery can be at 80% SOC and it is drawing well below the current that is available from my panels and hence charging very slowly. I know that the power is available because if I increase the load on the inverter the PV power rises to meet the load requirements while the charge current (reported by the BMS) remains unchanged.

When and how is the bulk mode activated? I have program 32 (Bulk charging time) set to Auto - but have no idea how that is supposed to work. There is an option for manually setting a bulk charge time, but that makes no sense to me because the SOC could be at any level when charging starts, so a specific bulk charge time seems useless. (I suspect this might be more useful for Lead Acid batteries)

With the days getting shorter now, my batteries are never reaching close to a full SOC. The low float charge voltage causes the charge current to taper off so early that I run out of sunlight long before the battery is charged. The problem is - there is still plenty of PV power available to fully charge the battery if only the charge current didn't taper off so early.

This thread was some much needed info! The bulk sucks. I thought of it as bulk charge to 57.6/ 3.6 per cell full. I think it just bulk charges to the float number you set and then float charges up to 100% soc or whatever you set.
I say that because after half a day of stand still I changed float to 57.6 and within a minute or two it jumped my voltage up to the float voltage and the cell voltages went up. Before that it was just staying the same for half the day and my shunt saw very little power if any coming in.

I still have not been able to also get 11 of my 32 cells to charge above 3.4v even with active balancing taking place. 10 or so cells just jumped up to 3.6 right away so I took the float back down after a minute or two. Even when balancing the 3.4 cells are not rising, just going down to 3.3 as the battery is used for heat sink fans and my fridge, etc and the 3.6 cells are lowering at a faster rate.

I'm thinking I just have some weak cells bc they are all basically uniform at 3.4 max and usually at 3.3v everyday while other cells fluctuate higher depending on settings.

I think I will just have "top" balance all the cells to 3.3 which is 70% soc. Just set 3.3x16= 52.8 as my max not 56.1 = 90% soc (battle borns' long life suggested bulk setting).

I loose about 10% soc a night (running 450w AC until about 10pm when the temps are lower in our high desert, and misc stuff like Batrium running on my laptop, etc. That still leaves me with 60% soc the next day. That seems safe than a bunch of cells getting to high.
 
This thread was some much needed info! The bulk sucks. I thought of it as bulk charge to 57.6/ 3.6 per cell full. I think it just bulk charges to the float number you set and then float charges up to 100% soc or whatever you set.
I say that because after half a day of stand still I changed float to 57.6 and within a minute or two it jumped my voltage up to the float voltage and the cell voltages went up. Before that it was just staying the same for half the day and my shunt saw very little power if any coming in.

I still have not been able to also get 11 of my 32 cells to charge above 3.4v even with active balancing taking place. 10 or so cells just jumped up to 3.6 right away so I took the float back down after a minute or two. Even when balancing the 3.4 cells are not rising, just going down to 3.3 as the battery is used for heat sink fans and my fridge, etc and the 3.6 cells are lowering at a faster rate.

I'm thinking I just have some weak cells bc they are all basically uniform at 3.4 max and usually at 3.3v everyday while other cells fluctuate higher depending on settings.

I think I will just have "top" balance all the cells to 3.3 which is 70% soc. Just set 3.3x16= 52.8 as my max not 56.1 = 90% soc (battle borns' long life suggested bulk setting).

I loose about 10% soc a night (running 450w AC until about 10pm when the temps are lower in our high desert, and misc stuff like Batrium running on my laptop, etc. That still leaves me with 60% soc the next day. That seems safe than a bunch of cells getting to high.
I had similar issues.
Changed the logic on Program 32 : Bulk Charge Time (C.V Stage)
from AUTO to 480 (8 hours)
I think its more getting it off Auto mode as that appears to make a bad choice and start Floating immediately.
Another thing, bank needs to be below Float for BULK charing to kick in, or so it seems to me....

Spoke with MPP Engineer, they suggested setting Bulk and Float to the same, as (we all know) this systems were not designed for LifePo4...
Not sure i want to do that, as common advice around here to still to use Bulk and Float for LifePo4. But in the interim i have set:
Bulk 56.8v (3.55v per cell
Float 54.5v (3.4v per cell)
Low Voltage 48v (3v per cell)

I set the bulk a little higher than i ideally wanted (3.5 per cell) as it does seem to stop Bulk charge a little prematurely.
Will keep an eye on it at things settle in. May go back to 3.5v per cell again if its behaves itself longer term

Hope some of that was useful !

From another thread, not sure if accurate, but another theory on the AUTO setting... :
I know that when program 32 is set to "Auto", the bulk charge voltage setting is ignored.
When set to manual it does not drop to float until the timer runs out. The timer starts when the float voltage is achieved.
This came up in another topic awhile back which you might remember.
 
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