I was playing around with the generators and I tried out TensionDropRPM
It works but the number I have to provide is not an RPM at all but he amps , and under it the tension drops.
For example I have this generator for a turboprop
generator.1= Name:StarterGenerator #Vrms:28 # PowerRating:5.6 #GovernedRPM:[curve.CurveStarterGenerator([data.simvar(TURB ENG N1:1, percent)])] #TensionDropRPM:100
With this curve:
curve.1 = Name:CurveStarterGenerator # Points: 10:0, 40:160, 50:188, 60:196, 100:200, 110:200 #Smoothen: 1
When I test this the the tension will drop exactly under 100 amps output.
I think this is reasonable and easy to set , but I went on a 2 hour trial and error because of the documentation. Also the RPM is not clear for the other prametrs in a way of what’s rpm ? Propeller, N1? N2? Right main gear ?
So this is my current setup that looks like works perfectly as far as I can tell.
I’m using TURB ENG N1:1 to drive the curve and as I noticed the TensionDropRPM value corresponds exactly to the point on the curve.
In this case at exactly 46% N1 the TensionDropRPM will go away and the generator can start producing properly.
And isn’t this what you expected?
The TensionDropRPM threshold value will be compared to the RPM value you provide with the GovernedRPM attribute, whether it’s a hard value, a simvar or a curve.
In your case, you provide a curve where 46% N1 corresponds to 181 RPM (whatever your unit is) and this is what the TensionDropRPM threshold will be compared to.
What can probably be misleading here is that you are free to use any units you want, as long as they are consistent.
My only issue is that the 181 in this case is not an “RPM” , the doc is confusing, in this case the 181 is ampres, as I said it works fine like this and absolutely makes sense, my issue was because the doc says “RPM” I was trying propeller RPMs like 1000 to 1900 and N1 Rpms 15000 to 30000 and I spent a good half day before I realized how it works.
I started to try N1 % rpms so 0 to 100 and I noticed something happening, than I figured it out.
Maybe a sentence in the SDK about what “RPM” is actually in this case would be helpful.
That is not what GovernedRPM expects.
It takes a rotational speed value. Your curve just maps the N1 value to a different rotational speed. It has nothing to do with amperes.
Some other aircraft will use RPM simvars directly:
generator.1=Name:generator_1 # Vrms:28.000 # PowerRating:11.200 # GovernedRPM:[data.simvar(GENERAL ENG RPM:1,revolutions per minute)] # TensionDropRPM:7425 # WearAndTearCollision:LeftWingDamageHigh,EngineLeftDamageHigh,NoseDamageMedium,TailTopDamageMedium,RightWingDamageLow,EngineRightDamageLow,LeftFloatDamage,RightFloatDamage,FrontLefFloatDamage,FrontRightFloatDamage,MiddleFloatDamage,RearLeftFloatDamage,RearRightFloatDamage
Where I agree the documentation can be clarified, is that you can use whatever rotational speed unit you want, not specifically RPMs.
We will add a note to the documentation.
Ahh I get it now, I just made my “rotational speed” the same as the amps output , and that is why they are the same. The sdk mentions that you can use any rpm but it was not very clear for me. Thx
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