Battery Monitor

[starcraft69]

I am looking at the Victron BMV-700 Battery Monitor. The shunt is installed on the negative side of the battery. My negative cabel on the battery go's directly to the frame I have no other negative wires connected to it. Will this still work?

[Sam_Spade]

stacaz822 wrote:


Interested in hearing what the "best" way to do it is.. I have been installing 12V and 24V DC systems in RVs and boats for many years, and have always run separate large gauge cables for the NEG side to all major devices, but also grounded the NEG to frame. Using Link 10 monitors, I have yet to notice much if any extra drain by only using the frame as NEG. The only problem with using frame as NEG is that it is more subject to corrosion on the connection, since they are usually exposed to the elements on the frame, underneath.

An individual wire for the negative connection.....to everything ......is much better, as you said above. Also having a frame connection should make things more reliable but can complicate troubleshooting and sometimes can introduce noise. Modern computer systems should NEVER have only a frame connection for one side of the power.

[babock]

Instead of the BMV-700, spend a few more dollars and get the BMV-712. It's a superior model.

I also believe the 700 is being discontinued by Victron.

[stacaz822]

Sam Spade wrote:

starcraft69 wrote:
Will this still work?

Yes. Exactly.
That's how most DC automotive systems are designed.

Not that it is the best way to do it but it's very common.

Interested in hearing what the "best" way to do it is.. I have been installing 12V and 24V DC systems in RVs and boats for many years, and have always run separate large gauge cables for the NEG side to all major devices, but also grounded the NEG to frame. Using Link 10 monitors, I have yet to notice much if any extra drain by only using the frame as NEG. The only problem with using frame as NEG is that it is more subject to corrosion on the connection, since they are usually exposed to the elements on the frame, underneath.

[starcraft69]

Thank you all for your input. I thought it was how it worked but just needed to hear it. Once again thank you

[Sam_Spade]

starcraft69 wrote:
Will this still work?

Yes. Exactly.
That's how most DC automotive systems are designed.

Not that it is the best way to do it but it's very common.

[DrewE]

starcraft69 wrote:

MrWizard wrote:
that means all your negatives , return thru the frame

yes this will work

Is this called a chassis ground? and is this also how the charging
works

Yes and yes. The negative output of the converter is also connected to the frame somewhere, as are the negatives for all the loads (either individually or collectively).

[MEXICOWANDERER]

Just a general semi-related question.

Have you located exactly where various hotel loads are connected to negative?

[starcraft69]

MrWizard wrote:
that means all your negatives , return thru the frame

yes this will work

Is this called a chassis ground? and is this also how the charging
works

[MrWizard]

that means all your negatives , return thru the frame

yes this will work