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Lynx Shunt vs. SmartShunt

Hi!

I'm building a new setup for a 24V system with Multiplus II for solar and wind. The battery system is flooded lead acid and I'm interested in monitoring the battery level and charge rate with a Cerbo GX. My question is about the following busbar setup I'm currently planning:


Left side: Lynx Power-In (4 IO slots)

1/ 24V battery system


Right side: Lynx Distributor (4 fused IO slots)

1/ Multiplus II 24V 3000VA

2/ Solar charge controller

3/ Wind charge controller

4/ Victron non-isolated DC-DC converter 24V->12V


It would be elegant to add a Lynx Shunt V.E. Can in the middle, but it would be quite expensive and the CNN-type fuse is crazy expensive. So my idea is to add a 500A SmartShunt between between lower negative bus and then a wire/plate between the upper positive bus. (On a side note, if the Distributor had 5 slots, I could only use that and put the shunt on the negative battery cable.)

Is there anything wrong with this setup for the intended purpose? Do I still need a separate fuse for the battery side?

smart shuntsmartshuntlynx shunt
3 comments
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On a side note, if the Distributor had 5 slots, I could only use that and put the shunt on the negative battery cable.

You could also use the end holes (left side) and add your own fuse for the 5th positive wire. Then skip the Lynx Power In if you have a single battery (and do not have more batteries in parallel).


Do I still need a separate fuse for the battery side?

I would fuse the positive wire between the battery and the busbar.

I use a HRC fuse (in a fuse holder/disconnector) on that wire. But it takes more space.

You could also use the end holes (left side) and add your own fuse for the 5th positive wire

That's a great point! I completely forgot about that. I'll skip the power-in then, because we only have a single series of a batteries for 24V.

What do you think about SmartShunt vs Lynx Shunt? Is there any difference in VRM functionality or other matters?

You have multiple options for a shunt: Lynx Shunt, a BMV variant or the Smart Shunt (cheapest option).


If you don't need VE.Can, get the SmartShunt (which uses VE.Direct).

VE.Direct has a lower limit for the total number of devices, but still plenty for "normal" systems.

If SmartShunt would be OK, but you also need the relay, get the BMV-712 Smart.


In all cases, for VRM you need a GX device (such as Cerbo GX).

1 Answer
Graydon avatar image
Graydon answered ·

Please someone correct any misinformation I may say, but I have used both shunts, and unless I am missing something, and/or, the Lynx Shunt has some new features to be added in the future, I would go with the Smart Shunt.


I have 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.


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