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daveb asked

BMV 712 is always showing 100% SOC and not recording any history other than charged energy?

My system consists of Victron Easyplus, Blue solar MPPT, CerboGX, Sterling B to B and BMV 712. Battery bank is a self build Lithium 280ah with Daly BMS. I have checked and double checked my wiring and settings and cant understand why the BMV is not operating as expected. There are no loads connected between the shunt and battery the BMS is on the load side of shunt. The BMV is permanent 100% SOC, does not show any AH Consumed and no discharged energy. The loads are the Easyplus in AES mode with a 240v fridge coming on for approx 3mins per hour with a load of 2.6a. The BMV seems in permanent charge condition with 18a & 250w even though there are no charge sources other the MPPT or Easyplus when on shore. So shows the same situation at night and without EHU hook up. Would appreciate help to sort this out it's driving me nuts.

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BMV Battery Monitor
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screenshot-2021-10-24-at-22139-pm.png (287.8 KiB)
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seb71 avatar image seb71 commented ·

There are no loads connected between the shunt and battery the BMS is on the load side of shunt.

Make a drawing of your system.

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daveb avatar image daveb seb71 commented ·
Correct, no loads between battery and shunt and BMS on load side of shunt.


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daveb avatar image daveb seb71 commented ·

distrobution-21958-pm.jpg

My Distribution - sorry don't have software to draw my system

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5 Answers
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seb71 answered ·

Disconnect everything from the battery, except for the BMV shunt.

The current shown by the BMV in this case should be 0A. Is it?

If not, make a "Zero current calibration" and check again if it is 0A when nothing else is connected to the battery.

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daveb avatar image daveb commented ·

Thanks for this. I did as you said and had only the shunt battery side connected and the + for the shunt feed and disconnected the feed from shunt to loads and also switched off + to distribution and it made no difference to Amp reading on BMV. As you suggested I did a Zero current calibration (several times) and it made no difference. So am I right to assume and please offer opinion, that either the shunt itself or the software must be falty

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seb71 avatar image seb71 daveb commented ·

If in those conditions the BMV is showing a non-zero current, it is probably defective.


You could try a "Reset to default" for the BMV (using VictronConnect, go to Settings and then use the 3 vertical dots menu and you have the Reset to default option) and also disconnect the power and reconnect, but most likely won't help. Still, easy to do.

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daveb avatar image daveb seb71 commented ·
Thanks again, yeah I did a reset to defaults and reset for my setup and its still the same. I bought in August via Amazon so although over 30 days hopefully I can get a replacement. Thanks for your help.
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daveb answered ·

The BMV 712 shunt was faulty and i've replaced with a smart shunt and everything is now operating as should. Thanks for all input.

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Kevin Windrem avatar image
Kevin Windrem answered ·

With loads, you should be seeing a discharge (negative current) on the BMV. Any chance you have the battery and load/system side of the shunt reversed?

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daveb avatar image daveb commented ·

Not seeing any discharge on BMV. Graphs in VRM show the discharge from fridge on VE. Bus DC Voltage & Current [276] graph. One of first things I checked was the shunt was in correct orientation and no other connections on battery side.

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seb71 answered ·

For the always 100% SOC issue, just in case you have some bad contact somewhere, disable the "Battery starts synchronized" from BMV settings.

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kevgermany answered ·

Looks as if your loads are being serviced by the Sterling B2B and other power sources, so the battery/shunt never sees the load, so nothing to see on the BMV except voltage.

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daveb avatar image daveb commented ·
What do you mean by "loads being serviced by ..."?
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kevgermany avatar image kevgermany ♦♦ daveb commented ·
Not from the battery, but by all the charging circuits connected.

So battery is at 100%, stays at 100% as the other power sources supply your load. You can check this by either disconnecting the charge circuits, or use a clamp meter to measure current from each of the charging sources.


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daveb avatar image daveb kevgermany ♦♦ commented ·

Thanks for feedback. Ah, now I understand and will check by disconnect and clamp meter to see if loads being met by other charge sources which I doubt as i have same reading of current and power on BMV at night when no MPPT activity, not driving so no charge from B to B, and no EHU so no charge from Easyplus charger. If i disconnect "Has DC System" in CerboGX and set Easyplus as Battery Monitor I do see a reduction in SOC overnight to 95% on VRM which is the usage of the Easyplus in AES mode and fridge. BMV though still shows 100% and no AH consumed. I wonder if i have a faulty shunt

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