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billy-myers avatar image
billy-myers asked

SmartShunt + Temp Sensor = Any Cell Positive in Bank?

So my 16 LifePO4 cells are stacked on there side in 2 vertical columns because of space requirements. My question is, since the coldest cell in my bank is closest to the floor, can I connect the victron SmartShunt Temp Sensor to the lowest positive cell terminal in the stack (cell 8 so that I get the coldest reading from the bank or do I need to connect it to the end of the series of cells? I can't tell via the data sheet what the voltage requirement is for temp/shunt operation off this lead is. Given that there is definitely a temp difference between the top of the bank and the bottom and the variance is not constant, I really need to have it at the bottom.20221202-125450.jpg

SmartShuntTemperature Sensor
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3 Answers
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klim8skeptic answered ·

As per the Smart Shunt manual the temp sensor has to connect to the most positive cell.

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billy-myers answered ·

As per your reference, the term "most" is not stated and the diagram included as an example shows a single positive terminal as an option. If the shunt supports a range of 6.5-70vdc and < 1mA then I am able to supply that need in that range connecting to cell 8.


Not everyone's battery configuration allows for the final positive terminal to be the best placement for the temp sensor. Especially in large LifePO4 cell banks.

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billy-myers answered ·

I think the answer is correct that klim8skeptic posted. I realized that it's impossible for the shunt to read what voltage the bank is if I'm wiring it midway on the bank. Struggling with a BMS with a chort temp sensor and a shunt with a long one and trying to make it work. Was hoping for a magic fix that was never there.

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