ANCEL BM300 12V Battery Monitor, Bluetooth 4.0 Automotive Voltmeter with Charging, Cranking System Test & Alarm - Compatible for Solar Power Systems, RVs, Motorcycles, Boats, Cars, and Trucks

Easy to install. I've only used the corresponding phone app to monitor volts and state of charge. We're chasing an intermittent parasitic draw, so it's easy to check if the draw has been active or not. Instead of guessing and hoping that the battery has enough juice to perform a start, this device gives you actual data so you can make better decisions and get ahead of the problem.

This is a great product. It does exactly what it says it will do. Packed with enough features for you to monitor your battery’s performance or lack of. The app is very user friendly, once you take the time to explore, you’ll realize how much information is at your fingertips. Even when you’re out of bluetooth range, the information is still being stored and waiting. I think I was able to go as far back as five days and view my battery’s performance data. Customer service is excellent. If you ever have any issues, they will go to the extreme to help you. Believe me. Now the Bluetooth signal maybe an issue for some but don’t ask for more than many other devices cannot offer either. Plus understand that the module is inside your engine bay (in most cases). Just get it. I would like to thank my Ford F150 Powerboost members who introduced me to this nifty piece of equipment. Because of how my truck’s hood comes down very close to my main battery, I have to keep it on the side.

I bought 2 of these. They are easy to set up with Bluetooth and works about 30 feet away. They give valuable information with respect to battery performance and even record in a nice graph to be retrieved later for examination in Excel charts. They can show State of Charge, Voltage and Temperature. That in itself is good enough for most users, but it can also evaluate starting and cranking performance. The problem comes with location-labeling and trip information. (See photo below). My cars are a RAV4 and a 08 Fit. When locating these cars using the App, the labels on the cars are reversed displaying the Honda where the RAV is and vice versa. This also occurs when using the GPS on trips. Another problem is displaying the trips. Sometimes mileage is shown, sometimes not. (See photo). Distances from the cars is also wrong. Photo shows distance as over 600 feet, when in reality, is 45 feet between the two vehicles. The battery display is about .3 volts higher than actual. If these errors were fixed I'd give it 5 stars... it is still a good device for battery health if that is what you need.

It works even in the four pack of large 1150amp batteries I have in my truck and seems super reliable. The app for it has a lot of useful functions and is super easy to configure and understand. No pairing is required. The app sees the monitor automatically and just works. I literally had it installed and up and running in two minutes. Device itself is about the size of a pack of playing cards and Bluetooth range on it is good. If you’ve got a vehicle like mine where the gauge shows the charging rate instead of the state of the batteries charge this is a very useful device and the readings it gives where within .01% of what my Fluke multimeter says so accuracy is very good.

I wasn't looking for this monitor when I happened upon it on Amazon. I work in the motorsports industry and had not seen anything like this in the dealerships and shops I visit on a regular basis. And since I'm an electronics geek who's also in the motorsports field I had to try this. Before I ordered however I checked out the Ancel Battery Monitor App in the iOS store. There were only 4 ratings at the time with three 5-star ratings and one 1-star rating, the app looked promising so I ignored the one negative rating and ordered up. Once in hand I found the ANCEL BM300 Battery Tester/Monitor unit to be smaller than expected, measuring 3 ¾" Wide x 2" Long and 7/8" Thick. (Tapered design, see the pic below with measurements). The two lead wires are roughly 7" long with open clips on the end. To install I just had to hook up the leads to the positive and negative ends of the battery on my motorcycle. I then went into the app and expected to have to fool around with Bluetooth connections but the monitor had already paired to my phone and was showing the current battery voltage. Sweet! (see pic) From that point I started the motorcycle and the ANCEL BM300 showed the current charging rate and battery voltage with the battery voltage showing on a line graph. (see pic) I then ran the Charging Test and the charging voltage at idle and high RPM was shown. (see pic) The ANCEL BM300 will also perform a Cranking Test which shows the cranking voltage as a numeral and also on a line graph. Note: I like that the app shows good readings in Green and low or bad readings in Red. The Ancel also has a Trip setting which gives you a history showing times and duration for the vehicle (car, motorcycle, etc.) has been running. The app also has some more features in the System Set-Up allowing set two separate Power alarms at a % of your choice. These alarms will remind you once the battery is below the chosen percentages, I have mine set up at 70% and 50%. You can also choose to have a Daily Power Notification or Abnormal Cranking Notification. So far I am very impressed with the functionality and ease of use of the ANCEL BM300. The Bluetooth range is strong enough that I can check the battery status on my motorcycle from my living room with it being 30 feet away inside a garage with concrete block walls. The only negative I can think of is that as far as I can tell the Ancel Battery Monitor App can only work with one monitor at a time. If it worked with more than one vehicle I would buy one for my truck and my camper as well. I would also have an extra monitor to use for diagnosing battery/charging issues on the motorcycles and off-road vehicles I encounter for work.

2 minute install. Great software. Tells you everything you need to monitor your car's battery and charging system. Bought one for each car... software allows for multi vehicle monitoring. Only wish they had a wifi model...

Works great, other than the distance of the connection, it needs to be a wifi connection, also the leads need to be a bit longer like double in length and the spade fork ends need to be smaller, or allow us to put our own ends on, it was way bigger than it needed to be and could loosen up

This battery monitor turned out to be a huge upgrade for my John Deere riding mower, especially since I like keeping an eye on battery health before and after long mowing sessions. The compact shunt‑based design makes it easy to install without adding clutter, and once mounted, it stays out of the way while still giving accurate readings. The app connection was straightforward, and having real time voltage, current, and state‑of‑charge data available on my phone is a big improvement over relying on the mower’s basic indicators. The accuracy of the readings has been solid so far. Seeing actual current draw while starting the mower or engaging the blades gives a much clearer picture of how the electrical system is behaving. The Ah tracking is especially useful for understanding how much the battery is being cycled during use. For a small machine like a riding mower, this level of detail helps catch weak batteries early and avoid surprise failures in the middle of a job. Build quality is good, and the shunt feels sturdy enough for outdoor equipment use. The wireless connection has stayed stable, and the app interface is clean and easy to read. This monitor does exactly what I hoped: it provides accurate, real time insight into the mower’s electrical system without being complicated to install or use. It’s a helpful tool for keeping the battery in good shape and avoiding downtime, and it fits well into the routine of maintaining outdoor equipment.

Very useful. It help me to catch a issue in the cars alternador with the live data, and also with the data log.

Works well as advertised. Have to be close to car for information. Useful for seeing battery charge as car is prone for some reason to drain the battery. My only suggestion is the black and red wires be a couple of inches longer - it did fit but make it more fiddly.

Is een gemakkelijke manier om de status van je startaccu te controleren.

installed in about 5 minutes - bluetooth connected 1st time really easy and there it was the voltage of my leisure battery handy for when all the kids are using my battery to charge all there phones - it enables you to not damage the battery and run it too low - ok so it has a crank setting which i have no need for on a leisure battery but you can set it to notify you when battery gets low which for me after destroying two AGM batteries because we used to run them flat as i had no way of telling pre my solar kit is fantastic - good but of kit for not a lot of money. IF YOU HAVE A CAMPER THIS IS SOMETHING YOU NEED