Postby Chris Bradbury » June 3rd, 2012, 12:07 am
I would strongly advise against extending power leads by more than a couple of inches on any brushless system. Power leads as with the motors themselves are inductive and the modern brushless motors are essentially a three phase alternating device. What happens is voltage spikes are created by the esc as the phases switch, (and by spike think upwards of 200v even on a 3-4s set up) these spikes are very low ampage (remember there's a big difference between amps and volts) so the battery absorbs them before they can bounce back to the esc. If you extend the wires too much (the limit of length will vary from motor to esc, to brand etc as its down to the capacitors built in to them) then essentially you reach a point where the esc effectively no longer sees the battery and the spikes bounce back to the esc rather than being absorbed. This creates heat issues in the esc capacitors, along with voltage fluctuations and will result in a failure at some point. You may then argue that you could extend the three wires to the motor instead, but again you risk a similar issue, plus the additional problem that you may now effect the timing, which will also stop the motor running.
Now this is for brushless and is a side effect of the pulsing the motor goes through. Brushed is different and far less effected as the power is run smoother.
My advice, which I have done on models like this is to move the receiver battery further forward instead, or even use a bigger one too. Make the weight added to balance the model something useful rather than just extra lead.
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