SparkFun Forums

[stonely0]

Hi,

I am just starting build on my 1st robot track rover and while wiring it up I realize I made a mistake and am expecting my Servos and Receiver to goes up in smoke but… somehow it is not and I can’t help but wonder why it works… Anyone here can give me an explanation why no damage was done on my receiver and servos…

My track rover is powered by a 6 cell 1.2v NiMah AA size batteries (fully charge draws about close to 8v current) towards the brush motor controller board (Cytron smartdrive dual 10 (with UBEC) https://www.cytron.com.my/p-mdds10). This motor controller board is then connected to my RC Receiver (Frsky X8R 8 Channel RC receiver https://www.frsky-rc.com/product/rx8r/) via a servo BLACK/RED/White cable, which than power all my servos and switch. In one of the Receiver channel I plug in another battery pack of 4 x AAs 1.2v NiMah batteries with the intention of powering all my servos and switch.

However, I make a mistake of not removing the RED wire that run from my motor controller board to my Receiver. Meaning I am sending 5v (after UBEC cut off) of current to my RC receiver via the motor controller board, and on the one channel of my RC receiver I am adding another (at least) 4.8v of current to my receiver. In total there should be 5v + 4.8v (at least 5v when fully charge) = at least 10v now in my RC receiver but somehow everything still works and nothing fail. Shouldn’t there be some damage according to technical specs?

Anyone care to enlighten me?

Thanks.

[lyndon]

I've been pulsing a red LED with 60+ volts recently. It still works. The color when pulsed is orange instead of red, but besides that, you wouldn't know that I've been abusing it.

Running something out of spec doesn't mean it will fail right away. It just means that its behavior isn't guaranteed.