This is a handy and common battery cell voltage checker and low voltage alarm.
Plug it in to the balance connector on your pack, taking care to put the gnd's together of course, and the display will read off the total pack voltage, and then each cell voltage.
When using 2S-8S an alarm will sound if the cell voltage drops below the set point of 2.7 to 3.8v
To set the alarm level just press the button on the top, each press steps through 0.1v and eventually cycles around to "OFF", which should be obvious.
Suitable for Lipo, Lithium-Ion, LiMn, Li-Fe, and other chemistry that have around that 2.7-4.5v per cell voltage.
These guys are very common, I'm sure you've seen them around, well here you go.
