bms + hybrid

Joaquinsfy

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Oct 9, 2016
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Hi,

I have a pip4048MS , i'm duplicating the @hbpowerwall configuration, now i want to add a BMS, probably Batrium, but how it's connected the BMS if the same 2 wires are using to charge/discharge the battery??

Can some one made a little diagram to help me?, i don't know how to connect a BMS if you only have pos+ neg - cables from battery to charger/converter.

Thanks friends!
 

daromer

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Not sure what you are searching for.

If we take Batrium BMS as an example. The system alone will consist of the master unit (Watchmon) and X number of slaves (Longmons as example)
This basic system only monitor the voltages and if you get a shunt the current going in and out and will balance the packs either in idle mode or when going to high voltage.

So basically :
Inverter negative -> shunt -> battery negative
Inverter positive -> battery positive.

The Batrium BMS will then report back the current going in and out of the battery.

You can also add extension board and disconect the load and even controll some inverters from the BMS. There is some work being done to hook this up to the MPP type inverters too now.

Hope that cleared some parts out :)
 

Joaquinsfy

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Oct 9, 2016
Messages
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daromer said:
Not sure what you are searching for.

If we take Batrium BMS as an example. The system alone will consist of the master unit (Watchmon) and X number of slaves (Longmons as example)
This basic system only monitor the voltages and if you get a shunt the current going in and out and will balance the packs either in idle mode or when going to high voltage.

So basically :
Inverter negative -> shunt -> battery negative
Inverter positive -> battery positive.

The Batrium BMS will then report back the current going in and out of the battery.

You can also add extension board and disconect the load and even controll some inverters from the BMS. There is some work being done to hook this up to the MPP type inverters too now.

Hope that cleared some parts out :)

@daromer, thanks.

So basically :


image_cgaone.jpg


also i understand that there's is wires (slave, longmon) to every positive battery, in my case 14.

the batrium is connected to the common negative?

the batrium is connected to the common possitive?

How balance the batrium the cells, sending current to the positive directly via longmon?

i know my question are silly, but i need to be sure, that i understand how it works.

Thanks in advance.
 

daromer

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No worries. I know pretty well how it works since i have a test system running as well :)
I will be posting a very detailed video about how to connect the batrium system up with watchmon + shunt + mons in a few days. need to finalize some details

But:

Every mon need to be connected with its own 2 cables to each battery pack. When that is done you connect them all together. watchmon -> mon1-> mon2->mon....->watchmon
So the communication is a circle.
The Shunt is connected to its own port on the watchmon. Its documented on their site how thats done.
For mons: https://www.batrium.com/pages/how-to-connect-the-cellmon-modules-to-the-watchmon
The shunt:https://www.batrium.com/pages/how-to-connect-the-shunt-spf102mod-to-the-watchmon

The watchmon itself can either be powered from USB or from the battery bank itself. It tolerates 5-65V on the port 1 and 2. 1 being GND. (Also documented on the faq) Its the shunt that is meassuring the voltage from the bank and not the watchmon as such even though it do meassure the input voltage too.

Balancing is done by simply burning excess energy to heat. The mons itself have a certain set of resistorns used for this. Balancing is done in 2 scenarios:
Scenario 1: When you go above a set voltage. Ie the Bypass volt (CV9) This is also the max voltage the bank should be able to reach.
Scenario 2: If current voltage of the cells are above Nom cell volt (CV7) it will balance (use energy) from the top cells. This parameter will be moved to its own parameter in next version.

So it basically wastes energy and its only good for keeping it top balanced. There is also possible to see what cells that do have problem and be able to track that so you can spot which ones do have low capacity.

Good to read: https://www.batrium.com/pages/faq

If you have more questions just ask. I should be able to answer the most common ones i hope :)
 

Joaquinsfy

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@Daromer

understood, now i understand how the batrium bms works, it' burn the excess of energy in each to cell to top balance them.

I was thinking that the balance is sending current to low cells to top balance, but now i see how it works.

All the question are answered.

Thanks again
 

daromer

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:)

Yw.

Regenerative balancing is a bit more costly. Most likely 3 times more costly per mon.
 

MajStealth

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Apr 11, 2017
Messages
129
sounds like it would be cheaper to get some panels more then?
i am also interested in the batrium bms *cough* i was not spoiled by HB *cough* but the import fees will make it a grand..... even with just some longmons...
 

daromer

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Thing is that it should only balance on first start and every now and then. When it starts to draw that much energy that it start to "cost" you, you should look into why your packs is getting out of balance that much...

If all your packs are pretty even capacity wise you really dont need to be able to divert energy and bottom balance like active ones do. Personally i would like active balancing but on the other hand i have almost been converted :)

And yes 1 extra panel will cover that extra energy 10 times over :)
 
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