WonVon 400A Smart Battery Monitor - RV Battery Monitor with Shunt Support High/Low Voltage Programmable Alarm for Battery 0V-120V Support Bluetooth for 12V Lithium Sealed, Gel, Flooded Batteries

I installed this in my truck camper with an inverter/solar system installed. I used for about two weeks during hunting season. The instant amp usage did lock up once. I started my toaster, and it was froze.. Wasn’t showing the 40-50amp draw. I had to unplug/reset the control box to fix. (Not a big deal) Any use during that “frozen” period, wasn’t counted and threw off remaining capacity. Communication using Bluetooth has worked great. I will check battery condition from my phone, and not have to get up to look at panel. For me, a feature of convenience.. Not needed, but nice to have. The shunt is heavy, and didn’t come with a decent way to mount. I built my own buss/mount, and made the shunt bracket you see in pic. Be prepared to do some custom work when it comes to mounting the shunt as well. Overall, I like it. We shall see if it stands the test of time…

This product was easy to install with my rv solar setup using 4 100ah lifepo4 batteries. It arrived damaged, contacted the seller and they sent me a replacement the next day. It is very accurate and the display is easy to read. I love the Bluetooth functionality with this unit which makes it great for dry camping.

I'm fairly impressed with this little meter. Installation of the unit itself was simple. I don't have a good way of determining how accurate the current metering is, but I did check the voltage reading against a Fluke meter and that part checks out. Having Bluetooth connectivity with an app is a bonus as well. There are a few things that could be changed/improved:1) On the display, there are two arrows indicating current flow. These are confusing because when current is flowing TO the battery, the RED arrow pointing AWAY from the battery display is lit. When current is flowing FROM the battery, the BLUE arrow pointing TO the battery is lit. This seems backwards as it should be RED for DISCHARGE and BLUE (or any other color) for CHARGE. The direction is correct on the app though2) The mounting holes on the main module are right under the wiring connectors. The means you need to mount the module, then plug in the wires. In a tight mounting position (like mine was), it is hard to secure the module, then plug in the wires3) It was not clear how much power the module itself draws and whether that is accounted for in the display4) The display shows temperature in Celsius and there is no way (that I could see) to change it to Fahrenheit. You can change the units on the app though, although it doesn't stick and will reset if you restart the app. Also, mine doesn't seem to work correctly since it seems to always show 12 degrees C

This Shunt is a great unit and works just great as well.I mainly use it for battery capacity tests and its usability is great and works without any issues. Even after the power goes off at the end just get a charger connected and you can display the last values!Great product which does work great. I wish this unit could be connected with a Victron system ;-)

Update 12/18/22The State of Charge "%" that is visible on the right side of the monitor is absolutely innacurate. 90% is what it reads frequently even the voltage for the battery does not correlate to that. The only thing this is good for is to see the draw that my appliances are generating. It seems accurate in general for that measurement. It's a BIG ISSUE for this to not be able to do what it's designed to do though. Right now my entire van is out of power and I have to revive the pack with proper voltage to get it up and working. I blame it 100% on this unit for it's highly innacurate soc readings which are completely worthless, making this product 10 times too expensive for what it does. Either some product support or a complete refund would be nice to say the least. This monitor has really screwed me. makes me want to install a battery protect from victron and use a very simple battery monitor, not this one.For some reason the wires are way too small to put into the green connector which would put power into the top left. It requires three different small wires to go into the connector, yet there are none included in the whole package that come close to being big ebough. The only cable left over actually has no space to plug into, it's just extra. Very frustrating since that would be THE ONLY thing I would need to get this thing up and running. The app installed easily enough by going to it on the play store. Maybe I just need to give it a little time, find the correct wire size to plug into it, and then go from there. Sucks though, these reviews were sounding so convincing with the ease of installation and everything in-between.*Edit same night*I found a very small and narrow flat head to add (just one) wire as instructed in the video. I used 14 gauge and only about a foot of it. Since then, things have been looking up! I struggled a tad with getting the bms recognized (from my phone's settings) but the top right "search" will pull it up and get it going (it failed on the first attempt) but it seems to know what it's doing thereafter.I do believe I may have sized this in the high side. This 600a one is massive and heavy. I'm not sure how to size it actually and there definitely were no instructions or diagrams for matching that on the product page, so I may return this for the 400 which just seems more similar to my systems power. I'll have to check for sure. But I'm sold in this device now! Things took a quick turn! I'm still unsure if this unit will give my phone any warnings or actually be able to protect my battery if something goes awry, but we'll see! At least it has plenty of info to give me on the status of my battery via phone or display screen. Will edit this one later for a more solid user review. Minus one star for the complicated setup and multiple directions that links that aren't so smooth and straight forward. If it's performance blows me away with time, I'd look past that and give it 5⭐

If you’re doing a solar system and need a way to monitor power and battery usage it’s the best option I found without spending thousands of dollars. It allows you to choose any voltage from 0 to 120 V DC I have a 48 V system which is hard to find Stuff for. The only thing I wish that was different was it only goes through Bluetooth I wish I could connect to the Wi-Fi so you can read the percentage anywhere. But other than that it works flawlessly would recommend.

I have a 500A Renogy unit and this is far far better. The colour screen is attractive and its very accurate, even via the App. If you view it on a Android phone, word of warning. There is 2 apps. You want KG and not KL... as there is far more in depth info. Bluetooth is also very reliable unlike the Renogy shunt.The only negative, the shunt has no mount or housing so you have to figure out how to mount it. I used a plastic wiring joint box as it's insulated too plus the lead to the Bluetooth module is VERY SHORT so has to be mounted very close. A small set back to a impressive product.

Worked so well got a second for other solar system,