Burning out Receiver

I’m hoping this is a simple one but I’m having an issue connecting my electronics. I used an almost identical setup to Guldsteen except that I’m using 2x6S 20,000mah lipos. For the BEC I’m using a castle creations 2.0 waterproof. The other difference would be that I soldered the BEC to one of the batteries and not after the series connection.

I tested the setup with just 1 battery and it works well. However when I connect both batteries in series and bring it up to 12S, I have fried the receiver. I tested the output voltage out of the receiver at both 6S and 12S and it is a solid 5.2V, so I believe the the BEC is working properly. I believe that I’m connecting the terminals correctly and it works at 6S so at a bit of a loss what to do next.

Any help would be greatly appreciated!

when you connect batteries in series you increase the voltage.
How did you managed to have 5.2V in both ways?

The bec controls the output voltage.


I’m using a “y” connector from the bec to the receiver and esc.

The BEC you linked is rated to 12s so I would just connect to 12s terminals, not 6s battery.

Thanks I will give that a try.

@michion I gave that a try and I’m still getting sparking when the circuit is in 12s. The output from the BEC is 5.2V but between the receiver and the input to the ESC something is happening because they both are sparking.

Receiver - Basic FlySky
ESC - Flipsky 300A Seal
BEC - Castle Creations

This is driving me insane!

Did you know sparking when you connect your batteries is normal? You need to use antispark connectors to eliminate this. AS150 or XT90S are good options.

Maybe load a photo of your setup so people here can try and help.

Yes I was aware of that.
I’m using the Flipsky 280A Antispark and I upgraded the wire to 8 gauge.

Here is my setup (It’s not finalized but just using this for bench testing):

This is how I wire the connect the receiver and ESC:

The top wire comes from the BEC and the bottom is connected to the long wire from ESC and I believe I am following the polarities correctly.

Connect the power from your BEC to CH1 and also just the signal wire from the esc into CH1. You will need to rearrange the pins if you only have 3 pin connector.
I believe thats how I had them connected when I was using that type of receiver.

Good luck, let us know if it works.

Thanks! I’ll give it a shot