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FlyToday avatar image
FlyToday asked FlyToday commented

Fuelsystem Junction Setting

Hello. I have a junction in my aircraft that does need options, but whatever syntax that I try use to set the junction, it is just not setting and the SimVar stays set to 1 (Simvar Watcher Had: "FUELSYSTEM JUNCTION SETTING:1" AND SHOWED A NUMBER VALUE OF 1.0000) . Some of the syntaxes that I have tried are listed below.

Keep in mind all names below are simplified.

Here is an example of my Flight_Model.cfg where I define the lines and junction:

Line.1 = Name:InLine1 #Source:LTank #Destination:Jctn1 #FuelFlowAt1PSI:0.10 #Volume:0.24 #GravityBasedFuelFlow:10

Line.2 = Name:OutLine1 #Source:Jctn1 #Destination:Vlv1 #FuelFlowAt1PSI:0.10 #Volume:0.24 #GravityBasedFuelFlow:10

Line.3 = Name:OutLine2 #Source:Jctn1 #Destination:Vlv2 #FuelFlowAt1PSI:0.10 #Volume:0.24 #GravityBasedFuelFlow:10

Junction.3 = Name:Jctn1 #InputOnlyLines:InLine1 #OutputOnlyLines:OutLine1,OutLine2 #Option:InLine1,OutLine1 #Option:InLine1,OutLine2 #Option:OutLine1

Here is an example of several of the key events that I have tried:





I saw another post that mentioned that changes were coming to junctions in SU10, but not sure if there will be any changes to the key events.

Thank you.

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1 Answer

MV-JimStewart avatar image
MV-JimStewart answered FlyToday commented

The SDK is a bit misleading in describing the FUELSYSTEM_JUNCTION_SET event in that it refers to the junction index being the first parameter and the option index being the second parameter. It's actually the other way around (at least, it is in SU10b).

Assuming you're wanting to set junction.3 (you don't list junction.1 or junction.2 in your example), you'd want to use:

option_index junction_index (>K:2:FUELSYSTEM_JUNCTION_SET)

In the simvar watcher, you'd need to provide it with the proper junction index to watch, which in this example of using junction.3, would be 'FUELSYSTEM JUNCTION SETTING:3'.

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FlyToday avatar image FlyToday commented ·
Thank you, your answer works perfectly. To be honest, it makes more sense to have the junction number first (as the documentation states), but once you know the dirty little secret, it works as expected. Thank you for your help.
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