5PCS 2in1 1-8s Lipo Battery Voltage Tester,RC Low Voltage Buzzer Alarm,Battery Monitor Checker Tester for 1-8s Lipo/Li-ion/LiMn/Li-Fe

I bought these battery testers after seeing them featured on a YouTube video by the TheRcSaylors. That video showed how they work and explained how they can save you much money by being able to monitor your LiPo batteries quickly and accurately. I've been using mine on several batteries since getting them. They are easy to use and do their intended job. They are small and don't weigh much at all, so can be used in a RC plane to tell when the battery is approaching the low voltage range that could damage the battery. The warning sound is quite loud, and will do the job. I highly recommend these little devices.

Very happy with product. Works just like it says. Should have bought these a lone time ago. A must have for RC pilots.

They are super handy to have. With this 5 pack, you can keep one everywhere you may need it. Battery bag, near charger, in your vehicle, etc...

I purchased these monitors for my Bebop 2 quadcopter battery charger. The original charger failed so I purchased a generic LiPo charger from Amazon (basic 2 wire connection). I was hoping I could use the monitor standalone - connect negative to negative, and positive to 3S (3 cells) and get a readout on the overall health - no go, the readouts were erratic at best. I guess that's what I deserve for trying to use them for an application for which they were not intended. I disassembled my LiPo battery and derived the pinout of the connector. After correctly connecting each battery tap, the monitor worked as expected - showed voltage for each battery in sequence, then displayed the total voltage. As many have pointed out, the low voltage alarm is quite loud (read annoying) but luckily can be disabled via the push button (unfortunately it still beeps a few times on power-up). Overall these work as advertised and I'm satisfied with the operation. It would have been good to have a little more connection info in the description. As for accuracy, I compared the voltages read from the monitor to those from a digital oscilloscope against 2 batteries. BATTERY1 (2yrs) BATTERY2 (new) Monitor Scope Monitor Scope 4.24 3.82 4.15 4.20 3.96 4.02 4.12 4.00 4.26 4.36 4.20 4.40 12.4 12.20 12.4 12.60 Measurements were taken the same way - 3 taps to the monitor, and 3 probes to the scope (probe for cell 1, probe 2 - cell 1, and probe 3 - probe 2). So there might be some discrepancy due to the way the monitor subtracts values (or my math on the scope). At any rate, the monitor voltages are close. If anyone knows how to do the math to compensate for the internal resistance, series voltage addition, and loads - feel free to add comments. Final thoughts - make sure you hook up the cell taps or the monitor will not work properly.

Would not have had anything better

There are five testers in the package

Exactly what I needed for my batteries!! And came with multiple!! Great deal!!

If you have an rc car you will have one of those they work well and the low voltage alarm is cool

Good little product at a great price. Works perfectly in my rc planes.

バランスコネクターに取り付けて電圧が設定した電圧以下になると大きな音で知らせてくれます

This voltage meter gives precise measurements of lithium polymer battery cell voltage. The adjustable alarm is very useful especially on RC helicopters. It keeps you from having to guess how much voltage is left and prevents crashes from over estimating the amount of energy remaining in the battery. Great product.

Works well for voltages that are manually set and/or goes below the set limit, the alarm beeps. However if the voltage recovers i.e. goes above the set limit, the alarm still continues to beep and does not stop beeping. This is very misleading & irritating specially when flying edf jets, where there is a large amp draw on take off etc. and this unit starts beeping continouslly.

Funziona bene.