I have just installed a BMV 700 and after syncing twice the battery % starts at 100% and constantly drops. My smart charger is powered and shows stable activity. My question is this. My house battery negative cable is in series - connected to - the cranking battery with the shunt inserted in-line …

Sounds like your connection to the starter battery is wrong. Read this DIY section FAQ especially the diagram to show how it should be wrired. [image] Shunt / battery monitor not reading the correct SOC/ Amps, missing solar, decreasing daily or other misreading problems DIY …

Thanks PW Farnell for responding so quickly. So - my set-up complies with the diagram which has the BMV 700 shunt attached right next to the house battery with that negative cable going to the cranking battery. The following was the set/up when I purchased the boat:- the house negative cable attac…

280Ah is correct. Not sure what else could be wrong if everything is connected as shown.

[image] Brios: I have just installed a BMV 700 and after syncing twice the battery % starts at 100% and constantly drops. Best to give a screenshot of the BMV battery settings. And voltage set points of your charger. Also the house battery has not been properly cross diagonally wired for ev…

Thanks @water_rat for your observations. I’m really keen to hear about the way that the house batteries are cross diagonally connected. I purchased the boat in March and this is what I inherited. From the photo I uploaded can you tell me how the house batteries should be configured? I appreciate th…

Have a read of Wiring Unlimited for details, and look at this diagram. [Screenshot_20230208_072034]

Hi Water_rat - I finally understood (duh) - the positive should go to one battery and the negative to the other - instead my set-up (inherited) was both connected to one of the house batteries - many thanks. I have rectified that (which will help my battery longevity) and reset everything, but my …

I just found the previous reply by you Best to give a screenshot of the BMV battery settings. And voltage set points of your charger. I’ll try and get this info now.

I have emailed Sterling Power to request the voltage set-points. This is what I see in setup and because there are 70 settings I’ve given only the first 30 or so, as other than 01 - 280Ah, these appear to be all set Factory Defaults. 01 BATTERY CAPACITY - 280 Ah 02 CHARGED VOLTAGE - 13.2V 03 TA…

2 questions. Is the charger permanently charging the battery. If so there should be a continuous flow of current into the battery apart from when you draw a large load and the charger can not supply this. What amps is the device showing is flowing and is it positive or negative. A couple of though…

BMV Battery % Drops

Q&A and troubleshooting

pwfarnell 5 December 2024 18:48 2

Sounds like your connection to the starter battery is wrong. Read this DIY section FAQ especially the diagram to show how it should be wrired.

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BMV Battery % Drops

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