Are Zippy Lipos safe with a Castle MMM Speedy?

[MrMin]

Originally Posted by Pdelcast

The better the battery, the less ripple current ... so what we do is size the capacitors to something that is reasonable, and use a high switching frequency to optimize the capacitance (higher switching = lower ripple current.)

But, the enemy is ripple voltage -- and the better the battery, the less ripple voltage.

The switching is on the motors, not on the dc source. If the TVS spikes a big cap it should smooth it out - i suppose a batt is a big cap, so patrick and brian are correct. But I imagine when the motor throws too much back that the load has to be disipated somewhere....The bat is usually a good place. But cheaps batts will not handle it. Can't the excess be clamped off to a big resistor or light bulb or maybe some fireworks and pretty sparks ??

I notice also that patrick and brian never like band-aid solutions like fans and heat.. Rather be efficient and never generate the problem in the first place...typical two too good engineers :-).

[MrMin]

Originally Posted by MrMin

The switching is on the motors, not on the dc source. If the TVS spikes a big cap it should smooth it out - i suppose a batt is a big cap, so patrick and brian are correct. But I imagine when the motor throws too much back that the load has to be disipated somewhere....The bat is usually a good place. But cheaps batts will not handle it. Can't the excess be clamped off to a big resistor or light bulb or maybe some fireworks and pretty sparks ??

I notice also that patrick and brian never like band-aid solutions like fans and heat.. Rather be efficient and never generate the problem in the first place...typical two too good engineers :-).

Patrick -- quick question -- are you using a transorb to clamp the overvoltage??

[Pdelcast]

Originally Posted by MrMin

Patrick -- quick question -- are you using a transorb to clamp the overvoltage??

Yes -- but remember, there is a limit to how much power a transorb can absorb. They claim some really high amp clamps (which is true) but they can only absorb those high amperage for very very short periods of time.

[Pdelcast]

I like the idea of making it a configurable option. Richard and Jon (my main software guys) are out of town until Friday, but I'll forward them the postings here. I'm sure they could add the voltage ripple detection limiting as a option (checkbox option) in Castle Link.