question

andywb avatar image
andywb asked

SmartShunt showing the wrong percentage

Hello,

I have a pair of 165AH AGM batteries (Victron BA412151080), wired in parallel for a total of 330AH at 12v.

Recently the state of charge was showing 57% remaining, despite 209Ah consumed - i.e. it was showing that only 43% had been consumed, when in fact 63% had been used.

How can this be, please? Do I have a faulty SmartShunt?




A couple of days later, and without charging the battery, the SmartShunt started showing 100%. This was without intervention from myself and despite the fact that the battery was even further discharged - you can see this from the voltage level, which I did not notice at the time.

I now realise that I allowed the voltage to get low enough that the batteries may have been damage, which is extremely annoying considering I was relying on the SmartShunt to monitor them. I never allowed them this low when I was using my boat's simple voltmeter!

Have I done something wrong please, or is this a common fault of SmartShunts?




SmartShunt
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snoobler avatar image snoobler commented ·

While @Alexandra has given you the corrective action, I'd like to answer your specific questions:


How can this be, please?

You failed to properly configure the SmartShunt.

Do I have a faulty SmartShunt?

No. There is no evidence of a fault with your smart shunt.

Have I done something wrong please,

Yes. Again, you failed to properly configure your SmartShunt.

or is this a common fault of SmartShunts?

No. There is no evidence of a fault with your smart shunt.


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2 Answers
Alexandra avatar image
Alexandra answered ·

@AndyWB

You need to disable starts synchronised.

And set your charged voltage in the app.

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kevgermany avatar image kevgermany ♦♦ commented ·
@AndyWB

Just in case you get a surprise, these suggestions are good, but SOC will not show until the charged conditions are first met. After that, as long as there's a reasonably frequent full charge the monitoring will be accurate.

You can also set a low voltage alarm in the smart shunt. Look at the alarms page of the smart shunt settings.

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Trevor Bird avatar image
Trevor Bird answered ·

@AndyWB … you may benefit from watching this video. As previously mentioned you do need to set “charged voltage”.

https://youtu.be/0HG4GiH9su8

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