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lifgun avatar image
lifgun asked

MPPT Charging behavior

MPPT and charging behavior :

38 KW Valence battery bank with external BMS

Solbian SP 130 solar panels

SmartSolar Charger MPPT 150/35 Firmware 1.61

Almost all consumers are switched off.


During the night I have a very stable situation with a steady consumption of around 52 Watts, after the PV is kicking in the consumption is rising more or less parallel to the solar production. Only a part of the produced energy is going into the batteries. Does anybody has an idea if I have some wrong settings in the MPPT ? I somehow think it's not connected with the BMS. Thanks for any thoughts !img-5949.jpgimg-5948.jpgimg-5937.jpg


MPPT SmartSolar
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3 Answers
matt1309 avatar image
matt1309 answered ·

Hi,

A few questions about your setup.

  1. How are you monitoring the "DC Power" ie are you using a smart shunt to determine what power is going to those loads?
  2. And also how is your battery connected to cerbo/venus os. Is that monitored using a smart shunt or is the BMS itself plugged in/communicating with cerbo somehow.


My guess is that victron system is missing a piece of data. The equation would be

Solar produced - DC loads = Power into battery

I'm not 100% sure but i imagine Victron system needs to know at least two of those pieces of information to show information correctly and then it can calculate the 3rd variable to balance the equation above.

We know it knows how much solar is coming in because the MPPT is telling it however my guess is that it's missing the other two.


(Someone feel free to correct me on any of the above).






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fbi avatar image
fbi answered ·
  1. How are you monitoring the "DC Power" ie are you using a smart shunt to determine what power is going to those loads?

DC power is monitored and calculated by Valence BMS box (Shunt is integrated in the Box)

2. And also how is your battery connected to cerbo/venus os. Is that monitored using a smart shunt or is the BMS itself plugged in/communicating with cerbo somehow

BMS itself communicate with Cerbo throw VeCan


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fbi avatar image
fbi answered ·

DC power is monitored and calculated by Valence BMS box (Shunt is integrated in the Box)

WILL DOUBLE CHECK IF SHUNT IS REALY INTEGRATED IN THE BMS BOX..

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matt1309 avatar image matt1309 commented ·
That would be my best guess for the cause. I'm unfamiliar with connecting BMS to Cerbo/venus however I'd maybe also check that connection is correct.
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