Pioneer Supply off UBEC with LiFe backup

  • I am using the Pioneer for RX and battery redundancy on a 12s lipo set up (50cc equivalent).

    I want the main Pioneer power supply to be off the 12s flight pack through a UBec into battery terminal 1 .
    Telemetry is connected to the speed controller 12s pack.


    The backup LiFe will be connected to the Pioneer battery terminal 2.


    Is this OK and can I assign battery terminal 1 to always be the primary supply.

  • Yes, this is possible.

    I was using this a long time in the same manor.

    The only difference was, that I used a charging device, to keep the LiFePo4 up and running als long as BEC was working.


    I had 8.4V BEC Voltage.

    It is also possible to deal with 7.4 Volt BEC and a simple Diode to the LiFePo4.

    In this case the Voltage Drop in not so significant in the beginning after a BEC failure.

    Mit freundlichen Grüssen

    Kai Wimmer
    "Die einen kenn mich, die anderen können mich!"

  • Just to show how I did it:


    The Board is this one:

    https://www.microchip.com/en-u…pment-tool/MCP73X23EV-LFP


    Just the half of it which is for charging 2Cell Batteries.

    BEC is connected to Batt1

    LiFePo4 is connested to Batt2.

    Don't forget to disconnet the red wire for the ESC Channel !


    As soon as BEC fails the Voltage drops to the LiFePo4 Voltage.

    As long as BEC is working with 8.xxV the Battery is charged with max. 1A.

    The electronic in the device only takes the current from the higher voltage.


    So you always have a well charged Battery.