MSefi.com read only forum (Jan.15,2018)

Is this possible, Can MS deal with VERY high (150,000+) RPMS? I'd imagine the fuel table would look very odd, and the MAP sensor would be useless aside of monitoring EPR. Could you also make a safeguard with an EGT sensor to shut down or throttle back the engine if the Turbine Inlet Temperature got too high?

This would be a challenge, but doesn't seem inconceivable. The normal maximum RPM limit in the MS2 code is 65,000, so you'd probably need some sort of code change such as internally multiplying the RPM by 10. The EGT shutdown would also require custom code tweaks.

If this is in an experimental aircraft, please keep in mind that the MS was not designed with aircraft safety certification in mind.

No worries about aircraft safety. This is planned to be a stationary generator running on B-100. I can get more power extracted out of the Turbine than I can out of a stationary small diesel engine.

Matt Cramer wrote:This would be a challenge, but doesn't seem inconceivable. The normal maximum RPM limit in the MS2 code is 65,000, so you'd probably need some sort of code change such as internally multiplying the RPM by 10. The EGT shutdown would also require custom code tweaks.

Perhaps simply an ADC input, with an output that breaks an interposing relay in the FP relay circuit?

If Wikipedia is accurate, it seems the typical FADEC cycles through its main loop 70 times per second - that's WAY slower than the MS, so at least you're not short on computing power.

Instead of using up the CPU for the 150K RPM effort, maybe you could construct a simple little Op-amp circuit or 555 chip timer/counter. That way you could have the circuit count 10 or 50 or 100 or whatever cycles then send 1 output to MS. That way MS would have time to do it's normal magic.
That approach would work good for a "cone-head". If you're more of a "gear-head" instead maybe you could get two vernier scale indicators from a servo motor or something that could be installed "out-of-phase" so they could act like a divider. Or maybe a little planetary gear set to get down to numbers that give you plenty of time for processing.

hardline wrote:Is this possible, Can MS deal with VERY high (150,000+) RPMS? I'd imagine the fuel table would look very odd, and the MAP sensor would be useless aside of monitoring EPR. Could you also make a safeguard with an EGT sensor to shut down or throttle back the engine if the Turbine Inlet Temperature got too high?

Well, so it happens im an AME...
What engine is this ???