Simucube 1 external resistor

Has anyone installed a external resistor to the simucube board ? I understand i can install one (2.5 ohm, 50 watt). Looking into building a OSW controller myself for the second time. My logic tells me a external resistor compared to the onboard one would be more reliable. Any advice, comments and pictures would be appreciated, thanks.


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I never had a use for an external resistor on Simucube board. With the latest FW and hardware release, I have not seen one failure on the regen circuit, irrespective of using a 10nm, or 45nm, servo.

Make sure you set a FOV proper and load a proper profile (or set it up manually) before connecting the servo and you are good to go :wink:

Ok, thanks for the info Beano. Yea, it’ll be several weeks before i start to buy parts for the build, im just doing the research now.
Im sure more questions will come.
Appreciate the info.

All good, Mate, keep us posted on your progress.

Yes I placed an external resistor on my SC1 before they started to offer the ability to natively… The 20 w resistors on the new boards should be sufficient.

You will want to use a 2.2ohm resistor of come value above 20w… In anywise I am not sure it will make the system any better but may have some effect if you are using stronger forces. Basically it is there to absorb the regenerative energy from the Servo so it doesn’t damage components.

Thanks for the reply Brion. I use a Small mige servo and im happy with it. I dont crank up the force because for me that means i have to muscle in steering inputs which upsets openwheel cars. Im thinking of going with the NDR-480-48 psu to drive small mige. What is your opinion on this psu and small mige for Simucibe setup.


That would be the optimal PSU for the Small Mige. you only need the SDR if you are going with a Large Mige which puts more Amperage by a significant margin… The NDR is maybe even a little overkill for the Small Mige but it is better to be over than under.

Ok, sounds good.