I really wanted to like the Lynx shunt since it integrates nicely with the Power In/Power Distribution modules, but unfortunately after spending months tinkering with it, I had to go back to my old (very accurate and less expensive) Victron Smart Shunt. As someone already mentioned, no amount of tinkering will fix the SoC drift issue…trust me…I tried. I ran into an issue from the very beginning where the unit will completely fail when adjusting the voltage after noticing that it was off by 0.75V out of the box. I must say that Victron was quick to address the issue and their support was outstanding. Then the dreaded SoC drift started to happen and it got worse during the winter months when batteries rarely get to 100%. I try to top-balance my bank once a month and I kept noticing a SoC drift of 25-30%. At one point I decided to drain the battery down to 5% during an outage and at about 30% SoC according to the Lynx Shunt, my system shut down when the bank reached 47V. Every connection in my system has been torqued to spec with the correct wire size. Now that I’m back using the Victron Smart Shunt for about a month my system’s SoC accuracy is back to almost perfect. Such a shame bc I believe Victron makes excellent products, but for some reason they totally dropped the ball on this particular, very expensive, piece of….equipment. Hope Victron releases a firmware update in the future to address these shortcomings, but I’m not holding my breath.
Exactly the reason why I chose lynx shunt, the nice integration.
I lost all hope for a solution (firmware update).
The problem is already known a long time now and none action or response from Victron.
Did calibrate very accurate and error was in mine case 10% soc at the moment I got the low voltage alarm.
In my opinion, if a firmware fix would solve the problem they would have already done it. If I’m right, that begs the question of why they continue to sell it as is…. But that’s a different topic. Compare the shunt resistor of the SmartShunt or BMV shunt to the shunt resistor in the Lynx Shunt. They are very different pieces of hardware and where I suspect the root of the problem lies.
I totally agree with you about the firmware fix. I was actually thinking that the issue might be hardware related and not necessarily software/firmware (“easier“ to address). Appreciate you sharing the research you’ve done on this. I think the Lynx Shunt has so much potential, but it’s unfortunate how Victron continues to ignore what many consumers keep reporting on various forums. Other than the Lynx Shunt, I really like my Victron gear though.
Simple fix would be a 2 point calibration 0A (already possible) and a max amp calibration.
Say you can reach 200A than you should calibrate this point for max precision.
This would need only a firmware update to make this possible.
The shunt resistance should be linear and hopefully it doesn’t have too much temperature drift.
But in mine case with currents that max 150A negligible.
I my case the longer I go without fully charging to 100% the worse the SoC drift gets. After a month or so it could get as bad as a 25-30%. I usually set my discharge floor to 25% (when I switch to grid) just in case I need “emergency“ power. When experienced a power outage I thought I still had a good power reserve (250-300ah), so I was frustrated when my system shut down because of low voltage (47v) when the Lynx still showed ~30%. I decided not to mess with it and went back to my Victron SmartShunt.
Over the time period and SOC error the mistake would be 30W.
30W seems to me quite much for 6 JK BMS checking the batteries, but maybe I should measure JK power consumption,…