I have this ESC (https://m.banggood.com/it/FVT-CBWI120A-ESC-Brushless-Speed-Controller-For-110-and-18Series-RC-Cars-Skateboard-ESC-p-985970.html?cur_warehouse=CN) that did an annoying and loud beeping sound on startup. Because the sound is made by the motor my idea was to disconnect the motor for the first few seconds of the startup and then connect it again.
So I disconnect the first cable from the motor and then switch the board on, but the motor still beeps. So I disconnect another cable from the motor and this time I hear a spark from the point where one of the power cable is connected to the switch. To avoid other problems I reconnect the two cables and switch the board on (this is now the usual setup) but, even if the ESC turns on, when it should starts beeping it somehow “restarts” (there was maybe a short circuit).
Now I think that maybe the switch has been damaged, so I remove it and switch the board on directly connecting one of the power cables to the battery (something I did also when my previous switch was broken), and at this point the ESC starts smoking from the inside.
I later opened the ESC and noticed that one of the internal capacitors (there’s also an external one) was disconnected (not welded anymore), as well as some burning marks.
My questions: -what the heck happened to the ESC? It has worked just fine so far -is it possible that the main cause is giving power to the ESC without it being completely connected to the motor? -is any of my actions the cause of the failure? -the capacitor disconnected because of the heat that caused the smoke or its disconnection is the cause of the failure? -should I buy the same esc again? (I don’t think so)
Any suggestion will be greatly appreciated; thank you in advance!