HOBBYWING ESCs are pre-programmed for many different parameters.

I.E.: The Xerun 120A V3.1 ESC is pre-programmed on 12 different parameters:

• Punch
• Timing
• LiPo Cut-off etc.
• #12 is LiPo Cells and its default is auto detect (automatically detects the number of cells- 2s, 3s, 4s, 5s, 6s)

Auto detect works fine if you use 2s, 4s or 6s, but not on 3s or 5s for the following reason:

• If voltage is below 8.8v it may be treated as a 2S by the ESC
• If voltage is between 8.8 and 17.6v, it may be treated as a 4S by the ESC (3s is between these voltages)
• If voltage is over 17.6, it may be treated as a 6S by ESC (5s is between these voltages)

As result, if you are using 3S, its voltage is 12.6 which lies between 8.8v and 17.6v, therefore, ESC treats it as a 4S.

Default cut off is set @3.2v x 4 cells = 12.8v, therefore, the ESC automatically cuts off power even though battery is fully charged.

As result, please make sure to update item #12 (Lipo cell auto detect) if you use 3S or 5S lipo battery. 

Our engineers are looking into this issue and try to improve the situation. 

Team HOBBYWING 

Special thanks to Luis Garcia