Power Capacitor on 24v12 Simple Motor Controllers


I’m thinking about using the 24v12 Simple Motor Controller for a project. There are two things that I’m interested in finding out

The product page states that you can use a “larger” power capacitor if the power supply is a long way away from the board. In my application, the power source will be a very long way away from the board (maybe 60ft max). How much larger does one need? 1000uF? 2000uF? Should I think of having a step-down converter closer to the controller to avoid having the power supply so far away?

Also, these controllers will be installed in to a project in a very inaccessible place, so I want to be totally sure they’re as reliable as they possible can be - so I want to add a heatsink to help with that. That being said, with the power capacitor on the board one wouldn’t fit (as the axial sort goes over the chips that need heatsinking). Is there any problem with mounting the capacitor on the opposite side of the board (other than it’ll be a bit of a pain to mount).

And finally - what size heatsink would comfortable fit over the FETs and/or ICs that need heatsinking?



Using a few thousand micro farads worth of capacitance across the power inputs of your Simple Motor Controller seems like it would be reasonable since you power supply is so far away. I don’t think that adding a regulator right before the motor controller would probably be too helpful, and it might be hard to find one that will handle enough current if you use the controller close to its 12A rating.

You could install a capacitor on either side of the board or connect a few in parallel to the VIN and GND pins off the board (as long as they are still very close to the controller). We do not have any specific recommendations for adding a heatsink.


Great! I’ll give it a go with 2200uF and see how that works.

Having a “local” regulator could still be an option for other reasons - would mean I could use smaller gauge wires to carry the power with a lower proportional voltage drop. Though as you say, a regulator to handle the peak current would need to be pretty big, so might not be cost effective.

I guess I’ll get a board and measure the square where the FETs are and pick a heatsink that fits!