I can’t get my smartshunt to show an accurate reading. System ends up going dead at “48%” I can’t seem to figure out what the isssue is. I input all the settings from the battery manufacturer
Not enough information to help out.
Tell us what batteries you have, type, voltage, Ah rating, number in series and parallel and a screenshot of your settings.
Do you have 2 batteries in series and have put in 2 x battery capacity. In series you do not multiply battery capacity, so your batteries would run out at indicated 50% because that would be 0%.
1 Like
I have 4 200ah 12v lifepo batteries in series x 2 so 8batteries total. Wired for 48v
The bottom photo is from today. It does again but at 56% I then set the soc to zero
The SmartShunt should he working reasonable well. The discharge floor for lithium is typically 10% or 20%. If your system is going dead at 48% then you have some serious problems. Have you checked that each of the 12V batteries in series are balanced because one poor pack going off line because it is not balanced would be an issue. You really ought to do a monitored draw down if you are losing power at 48%. The other possibility is you have not wired the shunt up properly a d you have some power draw from the battery that is not being measured or you have a large zero error. See the manual for zero current calibration and this link for wiring.
That would explain the 50% discrepancy.
It was doing this before I changed the battery floor to 48% I was just playing around at this point
The batteries are connected to balancers
All the negative power flows through the shunt.
Yes. And yes… now I actually tried to remove the smart shunt all together. Batteries are at 52v and the inverter won’t stay on for more than a few seconds before displaying the Low battery alarm. The loads connected are minimal and this system has been working completely fine for over 6 months. No issues until now.
Are both battery strings working, disconnect them from each other, then see if they are showing the same voltage. Use them individually to see if they both work, making sure to recharge them to the same voltage before reconnecting. It is not unheard of for the SmartShunt to loose accuracy but the failing at 50% points towards one battery bank not contributing.
To followup on an earlier post of @pwfarnell
The batteries:
1.) Self built or retail
2.) Detailed spec of above (cell type, BMS, manufacturer if retail).
System:
Please provide pictures of your shunt and associated wiring to your battery (all bank elements), and to your system distribution board.