Is the Lynx Shunt going to get some better features?

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Graydon asked Jul 27, '21

Is the Lynx Shunt going to get some better features?

I had been using the Victron Smart shunt for over 8 months, and have been very very happy with it. I used the VE direct connection to communicate with the rest of the system (MPPTS, Cerbo & Multiplus), and it has worked flawlessly. I recently switched to a Lynx shunt (3 weeks ago), and quite frankly, was very disappointed in its lack of features, considering its a fairly new product.

With the Smart Shunt, I was using it to measure the top and mid point voltages of my 2s3p (24v/300A) system.

It also had a nice feature that you could reset and correct the SOC, should you have to shut the power off. (Both shunts loose SOC when disconnected from power). The Lynx CANNOT be reset to the last SOC, it only allows a 100% SOC reset, which is pretty useless.

The Lynx shunt DOES NOT monitor midpoint voltages or deviations, which is a feature I miss to be able to track if the batteries are becoming imbalanced.

Now, I do not know this for sure, but since using the Lynx Shunt I have had 3 occasions in the last week where the power from the Multiplus shut off due to one of the batteries dropping in voltage too low, under 12.5v. This never happened with the SmartShunt, and I am wondering if the Smart Shunt communicated the mid point deviations to the system, and it compensated in keeping the batteries charged and balanced?

2 hours ago, I reinstalled the SmartShunt to see if it indeed works with the rest of the Victron environment to do a better job of battery charging and maintenance.

Q. Are the features from the Smart Shunt going to be made available in the Lynx Shunt via a firmware upgrade anytime in the future

SmartShunt lynx shunt

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Answer 1 · 2021-07-29T22:26:55Z

Graydon answered · Jul 29, 2021 at 10:26 PM

I have some more details to add. After 3 days of running both the SmartShunt and Lynx Shunt on my system, and using the SmartShunt as the main system SOC monitor, it has since run much better. I now see a 5% discrepancy between the SOC of each shunt the Lynx being the higher Value. I will monitor this for another 10 days, but at this rate, there is going to be a significant deviation between the two. This would explain why my Lynx Shunt was causing my system to shut down due to low voltage situations. It was saying it was at 28% when in fact, it was probably less than 10%, and some batteries were probably at their BMS cut off voltage.

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Answer 2 · 2021-07-31T16:28:56Z

Graydon answered · Jul 31, 2021 at 04:28 PM

More info, and thanks to lots of good advice in this community for searching out some possible solutions.

Originally, I had the power feeds for my Cerbo attached to the Lynx Power In bus bars (left side of Lynx Shunt). This obviously draws some power, but, I didn't think it would be significant. I also have my SmartShunt powered directly from the POS battery terminal, again to the left of the lynx shunt.

I moved them to the right side of the Lynx Shunt, off the Lynx Distributor and did a zero current calibration on the Lynx shunt. Since then , the deviation has dropped significantly, to usually less that 2%. (The lynx shunt only seems to count SOC in 1.0% increments while the smartshunt counts it in 0.1% increments).

Doing a zero point cailibration, I shut off the MPPTS and the Multiplus, and calibrated. However, I have been reading that the Multiplus still draws 2W when power off? So doing a zero current calibration doesn't correct for the steady Multiplus power draw, nor the power draw from the Cerbo and the Smart shunt. In some articles, they say to 'disconnect the Negative battery cable', then calibrate????? well, how is that going to do anything, as once the power cable is removed from the battery, neither the Lynx Shunt, or the Smart Shunt is powered and able to work or calibrate anything?

still working on this...

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