# Victron Bmv 600 Or Nasa Bm-1 Monitorplus Wiring Query



## gnscloz (Oct 4, 2008)

hi i'm about to purchase one of the above battery monitors, anybody got any opinions of which is the better option?

my set up is
280 watts of solar power
3 x 110 ah wet lead batteries
sterling battery to battery charger
sterling 1000 watt inverter

also after studying both wiring diagrams i have a query, i undertand that the shunt connects between the negative battery terminal and the negative to the loads and no other negatives can be connected to either side of the shunt, my question is about my inverter does the negative have to connect to the load side of the shunt?

thanks for any advice
mark


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## DABurleigh (May 9, 2005)

Is cheaper better in your parlance?

Or put another way, is a Bentley Continental better for people than a Ford Mondeo? 

Treat the inverter just as a load.

Dave


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## gnscloz (Oct 4, 2008)

DABurleigh said:


> Is cheaper better in your parlance?
> 
> Or put another way, is a Bentley Continental better for people than a Ford Mondeo?
> 
> ...


thanks dave

just want the most accurate, i dont believe the most expensive is always the best thats all read a bit online and read the nasa is not always accurate, ie battery capacity can read 105% like the look of the nasa but its accuracy is more important 
mark


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## DABurleigh (May 9, 2005)

Well the accuracy is just down to how close YOUR batteries are to the algorithm the meter uses.

The NASA and Victron algorithms are different. But at least with the Victron you can enter different Peukert coefficients so that in effect you can match your battery to the meter.

That said, I'd settle for any meter that gives a 5% accuracy on capacity, so 105% per se doesn't worry me 

Dave


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## subfiver (Oct 15, 2011)

Do you want to know how many amps are going in or out of your batteries, or do you just want a fairly accurate gauge of the state of your batteries charge ?

I have a bmv600 on the boat, I also have a Smartgauge. The Smartgauge is adaptive, as your batteries age they hold less charge and the Smartgauge will reflect this. Simples to install, too...

http://www.smartgauge.co.uk/smartgauge.html

I'll probably install one in the m/h sometime.


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## coppo (May 27, 2009)

We have virtually the same set up as you regarding solar, B2B, inverter, batteries and had a Victron fitted, great piece of kit, there was a post a while ago saying the Victron was better, forgot the reason although I think the post was by Eddie Van Bitz. He said they only fit the Victron now.

Maybe a search will help.
Paul.


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## DABurleigh (May 9, 2005)

http://www.motorhomefacts.com/ftopicp-1155746.html#1155746

et seq

Dave


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## spatz1 (May 19, 2011)

if you want a very accurate reading of your battery state of charge and all other measurements simply fit two back to back gt power meters....

One reads in , one reads out of the battery and i have a couple of switches to disconect so i can reset it on a daily basis.....

last night i used 65 ah and i ve just switched the solar on (365w total ) and i can see.....

A max of 285w in (max of 20 a ) and the amp hours are rushing in ...

By the time 65ah is put back in the readings will be down to 8w and below an amp and its in pulse de sulphating mode and about as charged as i m going to get....

This is the only reliable method i ve found of knowing exactly whats gone in and been taken out and alows you to know how much useable power you have left in your batteries and state of charge.


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## coppo (May 27, 2009)

DABurleigh said:


> http://www.motorhomefacts.com/ftopicp-1155746.html#1155746
> 
> et seq
> 
> Dave


Ah, thats the one Dave.


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