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BrianG · 02.05.2010, 11:17 PM

Caps will help smoothen the spike, which will help reduce the peak somewhat, but what you want is a transient voltage suppressor, or TVS. It basically shunts voltages above its rating to ground. As you can imagine, a single device has limits, and there is a LOT of kinetic energy when stopping a fast moving vehicle on a dime, and so it can;'t handle the power and blows.

This is especially important when running at the ESC voltage limit because there is not much headroom. If a spike is, for the sake of argument, 50% higher than the battery voltage applied, a 6s setup will generate over 33v. A 5s setup will generate over 27v. As you can see, the 6s setup will work the TVS harder since it is already closer to the ESC rating.

You can run several TVS devices in parallel to help share the load, but even then, there will still be limits. A combination of running a little less voltage than the ESC rating, more gradual braking, and the addition of caps and TVS devices will go a LONG was to curb those pesky spikes.

	(#5)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	02.05.2010, 11:17 PM Caps will help smoothen the spike, which will help reduce the peak somewhat, but what you want is a transient voltage suppressor, or TVS. It basically shunts voltages above its rating to ground. As you can imagine, a single device has limits, and there is a LOT of kinetic energy when stopping a fast moving vehicle on a dime, and so it can;'t handle the power and blows. This is especially important when running at the ESC voltage limit because there is not much headroom. If a spike is, for the sake of argument, 50% higher than the battery voltage applied, a 6s setup will generate over 33v. A 5s setup will generate over 27v. As you can see, the 6s setup will work the TVS harder since it is already closer to the ESC rating. You can run several TVS devices in parallel to help share the load, but even then, there will still be limits. A combination of running a little less voltage than the ESC rating, more gradual braking, and the addition of caps and TVS devices will go a LONG was to curb those pesky spikes.