After 6 months of use it dropped dead.
Looking at the forums history i see many others as well..
I thought i bought a quality product from a respected company.
What is your system voltage?
There is a known issue with 48V and you should get a replacement.
Just contact your seller/installer.
Is it possible to use the victron precharge cable to slowly power up the smartshunt 300a initially with 48Vso it doesnt burn out? Or it will happen regardless for certain units?
48V
The inverter is a MP 2 3000 GX.
I’v contacted seller, does not seems to care, and if he would replace it, it will break again like it did (2-3 times!!) to other members here
The system keeps running without the shunt, i’ll handle without it.
Take this series off the shelfs and try to design a more reliable products, your name on the line.. i won’t buy victron again.
Could you elaborate on this issue please, to assist in giving the supplier known producer information for any replacement of this.
For instance i have a 300a shunt on 48v system and if there is a known issue it would be good to know if this issue is production date / serial number related etc to ensure replacement is forthcoming.
Are dealers/ all suppliers aware of the known issue or where is this known issue data to be found?
No need to assist. Send back for an RMA. If it is known issue then it doesn’t require much except following the protocol.
If your supplier is not listed on the where to buy then the next in line is the distribution centre which can be traced with the official support form
Your seller or to be more precise the responsible distributor should know about that problem.
There is a “repair kit” with a capacitor to prevent a it from failing and there is also an improved hardware version (I’m not sure if that is already available to order).
Devices within the affected SN range are replaced under warranty.
Since I’m a customer outside the EU, I’m assuming my replacement Shunt will be from the same series as the old one. Just like what happened to others, I’m worried it’s probably going to fail again.
I wanted to ask a few things to try and prevent this:
- Are there any specific operational steps I should avoid so it doesn’t burn out again?
- Before disconnecting or turning on the inverter/battery, do I need to disconnect the shunt’s positive cable from the battery? Does the inrush current during this process damage it (due to a design flaw)?
- Would it be a good idea to add a capacitor and a resistor to create a sort of snubber circuit between the battery and the shunt?
I think this information could be really helpful for anyone else seeing this post who wants to avoid the same issue.
@BH1 - You describe that “suddenly” the shunt was not working anymore. Did something happen before? Was the system turned off, the breaker in the battery turned off/tripped.. anything?
The inverter and battery breaker were turned off for a few hours and then turned back on. There was no smoke, no pop, and even the shunt’s original fuse is still intact.
It’s something I’ve done dozens of times before without any issues.
The official fix for the affected units is to add a 10µF 100V Elco in parallel with the positive connection.
This will not fix an already broken Shunt.
I appreciate all your help
OK, so you could retrofit that externally on any shunt. Or could that potentially cause problems if you retrofit the external capacitor on newer shunts that aren’t actually affected by this issue?
I have raised a support request for my shunt, as currently it is unknown if my shunt is affected, as currently no information has been given for affected units.
Bit confused on you state a repair kit is available and also official fix is to add a 10uf capacitor.
When / who / how is this to be done and to what?
2026-03 - SmartShunts power supply issue in 48V systems - v1.pdf (4.1 MB)
I thought this might be useful for you guys.
Thanks for info.
Pity it wasn’t made public previously or was it?
Still cant work out why a shunt needs it if purchased unused/new, but a in service shunt dosnt need it?
According to the information, every shunt (except those manufactured from July 2026 onward) needs the capacitor in question if the shunt is operating in a 48V environment.
The potential failure can occur when the inverter is switched on after the system has been shut down and the inverter’s capacitors have been completely discharged. At that moment, the inrush current is high and creates a voltage spike that can damage the shunt.
Victron claims that the probability of this happening is around 1%, but all shunts operating at 48V are potentially exposed to this issue.
Clearly states:
"When to install the capacitor Recommendation: • Replacing a failed SmartShunt: Always add the capacitor. • New 48 V installations: Adding the capacitor is recommended. • Existing, operational systems: No action is required. There is no need to plan or conduct special installer visits solely to add the capacitor to working installations. "
So i’d disagree.
Agreed.
I realized why we’ve never seen this issue on any 48V system we’ve installed. We ALWAYS install a pre-charge circuit in our systems. If we’re using Victron LFP NG batteries with a Lynx BMS, the pre-charge is already included. Even though some of the other commercial 48V batteries have pre-charge circuits built in, we always install our own and include the pre-charge in the startup procedure we document for customers.
Your disagreement won’t prevent additional shunts from older series from failing in the future. It’s true that the probability is not particularly high and that certain conditions need to be present, but the fact is that it has happened and will probably happen again under certain conditions.
At least now we know what is causing the problem and how to prevent it.
What Victron means is that if it hasn’t happened to you so far, then the conditions required for the failure are probably not present in your case (a non coiled cable, a 12V or 24V system, a soft-start circuit, etc.), and therefore there is no “need” to add a capacitor.
Mine worked fine for 6 months before failing. It’s your call..