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2 questions about position of Smartshunt and its connections

Dear Victron-fellows,


I have 2 questions about adding a Smartshunt to my system. The picture displays a simplified situation: 2 batteries in parallel, fed by a dynamo, Multiplus and MPPT (via Argofet). Now I want to add the batterymonitor and 2 questions have risen:

- Does it make a difference (or is it good or bad) on which of the 2 batteries the VBatt+ of the shunt is connected (A or B in the drawing)?

- I know I have to connect the shunt to the battery-minus without any other connections on that side. Since I have 2 batteries in parallel, I suppose the right position is C? Problem is that there is hardly any space over there where the minus-cables comes together and I have to use long(er) cables. On position D it would be much nicer (together with A for the powersupply / +). Is this a go or a no go?

Hope to hear from you

Kind regards,

Pim

accu-opstelling.jpg

BMV Battery Monitorsmartshunt
accu-opstelling.jpg (836.4 KiB)
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1 Answer
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seb71 answered ·

You need another negative busbar. You connect the two negative wires from the two batteries to it. Then install the shunt between this negative busbar and the nevgative busbar from your diagram (following the correct orientation of the shunt).


The positive lead from the shunt can be connected to the positive busbar (unless you will use the one with a temperature sensor, in which case, connect it to the positive terminal of one of your batteries).

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Alternatively, you can install both negative wires of the two batteries on the "Battery minus") terminal of the shunt and the "load" terminal of the shunt will be connected to the negative busbar from your diagram.

But using two negative busbars with the shunt in between is better.

Hello Seb, indeed and an extra busbar is not necessary because the result is the same then I think? The present busbar is used for the negatives of both batteries and from there a cable from the bar to the Battery-minus side of the Smartshunt (which is the same as connecting both cables together on the battery minus pole of the Smartshunt) and from there the System minus of the shunt to the loads? So in fact the same as in the picture at position C?

It is not a good practice to put many wire lugs on the same bolt. Maybe two, but not more.

It is much better to use busbars so that each wire is connected at its own bolt.


On the battery side you have two wires (one from each battery).

On the load side you presumably have many more wires (charger, inverter, other loads, etc).


So if using only one negative busbar, from my point of view the logical position would be on the load side of the shunt and not on the battery side of the shunt.

It's your choice.

And also you must use fuses for all positive wires.