Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Sylvestre on October 11, 2011, 06:27:18 PM

Title: Capacitor Values To Reduce Electrical Noise?
Post by: Sylvestre on October 11, 2011, 06:27:18 PM

Hey guys,

I have two motors that require 18 amps.  I am using a Sabertooth 2x25 motor driver to control these motors and have a 24 volt 55 AH.  Can I just use three 0.1 uF to reduce the noise?  If not, what should I use?  I am using these motors  http://www.monsterscooterparts.com/24v-350w-motor-11-tooth-25-chain-my1016.html (http://www.monsterscooterparts.com/24v-350w-motor-11-tooth-25-chain-my1016.html)

Title: Re: Capacitor Values To Reduce Electrical Noise?
Post by: newInRobotics on October 12, 2011, 03:19:00 AM

Have a look at Value of damping capacitor for DC motors (http://www.societyofrobots.com/robotforum/index.php?topic=14602.0) thread  ;)

Title: Re: Capacitor Values To Reduce Electrical Noise?
Post by: Sylvestre on October 12, 2011, 12:26:46 PM

I have looked at this and it didn't really give me what I was looking for.  Can I use 0.1 uF capacitors or will I need capacitors of higher value?

Title: Re: Capacitor Values To Reduce Electrical Noise?
Post by: newInRobotics on October 12, 2011, 01:34:18 PM

By the way, isn't Sabertooth 2x25 (http://www.dimensionengineering.com/sabertooth2x25.htm) a regenerative driver? If so, it already has two large caps to absorb spikes and compensate voltage drops. You can also add 100nF cap between motor terminals to fully filter out high frequency noise. Also, as suggested by Soeren in the before mentioned post, motor housing should be grounded by low impedance path and both terminal connected to it via 100nF cap.

Title: Re: Capacitor Values To Reduce Electrical Noise?
Post by: Sylvestre on October 12, 2011, 04:30:52 PM

Ok thank you.  Yeah I thought this was protected by the Sabertooth.  I just wanted to make sure.  Thanks for your help!  :)