???? motor capacitors ????

[harry697]

I plan to hook up an old Novak 410-mxc in one of my vintage cars. I'm a little confused about the three 0.1uf capacitors that Novak says you must use on all motors. In their instruction manual it says that the esc can be damaged if all three caps are not installed because of spikes that the motor can cause. But everywhere else I read, it says that the caps are to filter "electronic noise" that can cause radio interference.

So I guess my question is, do you still need to run the capacitors even if I use a DSM radio?

Also, I have a few motors that claim the capacitors are built-in and there is no need to solder any on to the motor. How true is this in regards to the 410-mxc?

[8rad]

So I guess my question is, do you still need to run the capacitors even if I use a DSM radio?

I have wondered this myself. I always add the caps regardless of the receiver being used. 2.4 radios are probably less susceptible to motor noise but better safe than sorry. And yes some of the later brushed motors came with the caps in the end bell. In this case you dont need to add caps.

I have never added caps to protect the esc only for the radio noise. Maybe they were worried about damage to the input of the ESC from the reciever.

[harry697]

Thanks for the reply.


Can anyone else confirm whether or not the esc will be damaged if running without capacitors? I know it's not a big deal to solder some on. Just wondering if it's necessary with today's 2.4 radio systems.

I surely don't want to fry this vintage piece.

[THEYTOOKMYTHUMB]

I can't imagine it damaging the esc, but certainly can't state that in any scientific way. I don't think noise would be an issue either. I do think the motor would have a smoother power band with caps on though.

[8rad]

I dont think you will damage the ESC. I have never known an ESC to be damaged from not adding motor capacitors.

[Mad Racer]

Diodes are important not just for motor noise but to stop voltage spikes back into the esc.

More important is the bigger diodes for that reason. As you coast into a corner or apply brakes the motor acts as a generator and puts voltage back into the esc. Nothing wrong with that but voltage spikes can damage the esc.

Some Esc has the caps inbuilt but to save space they started not too.

Novak Cyclones operate at very high switching speeds and they really need them. The later model GT7 have a small circuit board with diodes & caps wrapped in shrink wrap on the one of the motor wires for this reason.

As for radio noise spectrum radios operates way above any noise the motor can make. Noise won't make any difference at all. If your caps are knocked around they can cause more problems than they worth.