Rev Limiter User Advisory

For people running FreeEMS to discuss it and ask any questions about using and adjusting it.
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Fred
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Rev Limiter User Advisory

Post by Fred »

If you have a seemingly noisy RPM signal in your logs, ensure that your rev limiter hysteresis is greater than the variance in your RPM. If not, it will cut in and out too quickly potentially causing harm.

I noticed this while viewing a log of Sim's and spotted his fuel cut limiter in action at the end of most gears. Of course, he has no injection, so no big deal, but the same would happen at higher RPM for ignition. In that particular case, it could be a good thing, but for injection it's a bad thing.

Fred.
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Fred
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Re: Rev Limiter User Advisory

Post by Fred »

On the slow ramp up side (slow in the snot rocket, anyway), there is time for it to oscillate in and out of cut. Obviously if it was cutting it would fall more violently and thus be less eratic, but it'd still not be ideal. The down side is faster so doesn't experience this "sitting on an edge" effect.

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DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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