Installing a Victron battery monitor

[zmsakas]

Hi all! Just bought a Victron battery monitor (BMV 712). Does anyone have tips for installing? We have two 12V deep cycle batteries in parallel.

Would greatly appreciate any instructions or advice. The manual isn’t very helpful.

Thank you!
Zoe & Paul

[daleyocum]

Try searching Youtube for “install bmv712”. You’ll find all kinds of helpful videos.

[rowiebowie]

Originally Posted by zmsakas

Hi all! Just bought a Victron battery monitor (BMV 712). Does anyone have tips for installing? We have two 12V deep cycle batteries in parallel.

Would greatly appreciate any instructions or advice. The manual isn’t very helpful.

Thank you!
Zoe & Paul

I'm surprised by the poor instructions, but install is fairly basic. You will need new negative cables as the shunt must be installed on the negative cable between your batteries and your inverter charger. In my case, I replaced one 48" negative cable with two 24" cables and the shunt in-between.

You will also need to install a small postive "b+" cable from the shunt to the positive battery terminal. Then decide where to mount your display (unless it is bluetooth enabled).

[zmsakas]

Originally Posted by rowiebowie

I'm surprised by the poor instructions, but install is fairly basic. You will need new negative cables as the shunt must be installed on the negative cable between your batteries and your inverter charger. In my case, I replaced one 48" negative cable with two 24" cables and the shunt in-between.

You will also need to install a small postive "b+" cable from the shunt to the positive battery terminal. Then decide where to mount your display (unless it is bluetooth enabled).

Thanks Rowie!

Our confusion comes from needing to attach the monitor to two batteries in parallel when the instructions show just one. Any tips on that?

[uwe]

Originally Posted by zmsakas

Thanks Rowie!

Our confusion comes from needing to attach the monitor to two batteries in parallel when the instructions show just one. Any tips on that?

Look to that negative side of your parallel wiring. The black wire ( most likely black) will go to from batt 1 to batt 2 and then to a grounded stud, possibly through the power center. You need to find the last leg of this negative wire before it connects to the vehicle ground, and insert the shunt between the ground connection and the batteries or power center. Only then will the shunt be able to measure current correctly.

[uncle_bob]

Originally Posted by zmsakas

Thanks Rowie!

Our confusion comes from needing to attach the monitor to two batteries in parallel when the instructions show just one. Any tips on that?

Hi

The two negative terminals on the batteries stay connected to each other.

The two positive terminals on the batteries stay connected to each other.

The two battery negatives ( already connected together) go through the shunt and *then* to ground. When you are done, the *only* thing connected to those two negatives should be the shunt. All the wires that used to go to the battery negatives now to to the "other" side of the shunt.

The positive side stays just like it's always been.

Bob

[SanJoe]

Originally Posted by zmsakas

Thanks Rowie!

Our confusion comes from needing to attach the monitor to two batteries in parallel when the instructions show just one. Any tips on that?

I installed mine on two parallel batteries...Since both terminals are at the same potential (shorted). Just treat the setup like the single battery. The lead coming off to supply the trailer is where you place the shunt. The positive, as mentioned can go to either.

[Trons4u]

The shunt always goes between your inverter and the battery that's connected to it. If there are other grounds going to the neg battery post, they need to be removed and connected to a bus bar, then you run a battery cable from the bus bar to the neg battery post. All grounds or negatives need to go through the shunt, that's why the need for a bus bar.
It doesn't matter if you have two or ten batteries, the shunt always connects between the inverter and the first battery (negative). This way anything that is using power will be in the 'loop' and you will get an accurate reading on the BMV.
Here is a link to a video that Tom from

Mortons on the Move

did, he does a really good job of explaining things.

[AirGT65]

Since you have two batteries, be sure to insert the COMBINED amp hours for both during the setup process. That will let it to correctly calculate the total charge remaining after a drawdown.

[rich.dev]

Here’s a schematic layout of how to connect the BMV-712 to your batteries in parallel.

[Skyhook]

Has anyone installed a Victron Smart Shunt? I have just purchased one and also find the instructions misleading. It says the shunt is not waterproof. So a "waterproof" enclosure must be added either in or on the battery box. Also, Victron shows that the shunt has to be mounted between the battery - and any other attachements. A bus is needed?

[Skyhook]

This is the factory snarl that is my battery box.
The battery layout has a load side and a charge side apparently. The monitor wiring diagrams only show parallel battery connections not in and out.

[KSA63]

Nothing like a picture to help out. Shunt installed in Battery Box. AGM 210Ahr installation.



Stays dry so far but I will be putting a rubber strip over top of it sometime just to protect it a little better.
Kevin

[solomon.m]

I put my shunt in an external waterproof box and ran the cables in through gland nuts. Here a few pics. This install heavily leveraged several threads in the Forum, always a great reference.

[jeffmc306]

Zoe and Paul,

I documented my BVM-712 installation here

I also installed a battery disconnect inside the battery box at post #10.

Good luck with your install. Hope that helps!
Jeff

[Skyhook]

Thanks for the pictures, it looks like a great job. Very neat. What are the other devices in the box?

[KSA63]

Originally Posted by Skyhook

Thanks for the pictures, it looks like a great job. Very neat. What are the other devices in the box?

In my case, there is only the shunt and one other device in the battery box. That would be the 100 amp fuse/link for the 1000w inverter in the one positive lead. This is a factory device.
Kevin.

Oops, I see you were referring to another post... oh well.

[KSA63]

Just adding a picture of the new rod, washers and nuts used to tie down the batteries as I did not have that in place when I took my pics above. The batteries are Stark Energy 125AH and they barely fit in the box. If they ever swell up I likely won’t get them out without cutting the top of the box off. So the space between the batteries was substantially reduced and I could not hold the batteries down with the original tie down.

[uncle_bob]

Hi

Looking at how the shunt is built, I mounted it inside the trailer. Based on how it's built, it would take a *very* fancy enclosure to actually protect it out in the spray coming off of the tires and road. Hermetic feed throughs are *way* more expensive than a couple foot long piece of wire ..... (and yes, that's based on 40+ years of experience designing stuff that *did* pass the military testing for that sort of environment ....)

Bob

[s1000pre]

I ended up returning mine. The shunt/batteries etc. we’re not the issue. The issue was running the wires from the shunt into and through the trailer to a convenient spot for the monitor. I didn’t feel like tearing up my new Airstream or having exposed wires anywhere.